imports pep8'ed and optimized
diff --git a/.travis.yml b/.travis.yml
index 9f6ea31..b806fe1 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -14,7 +14,7 @@
 install:
   - pip install codecov
   - pip install -r requirements.txt
-  - pip install --no-deps .
+  - pip install -e .
 script:
   - PYTHONPATH=.:$PYTHONPATH python tests/__main__.py
 after_success:
diff --git a/CHANGES.txt b/CHANGES.txt
index f74fcd4..83ad7b8 100644
--- a/CHANGES.txt
+++ b/CHANGES.txt
@@ -1,8 +1,9 @@
 
-Revision 0.2.1, released 21-11-2017
+Revision 0.2.1, released 23-11-2017
 -----------------------------------
 
 - Allow ANY DEFINED BY objects expanding automatically if requested
+- Imports PEP8'ed
 
 Revision 0.1.5, released 10-10-2017
 -----------------------------------
diff --git a/pyasn1_modules/rfc1155.py b/pyasn1_modules/rfc1155.py
index 4980a38..69c160e 100644
--- a/pyasn1_modules/rfc1155.py
+++ b/pyasn1_modules/rfc1155.py
@@ -12,7 +12,10 @@
 # Sample captures from:
 # http://wiki.wireshark.org/SampleCaptures/
 #
-from pyasn1.type import univ, namedtype, tag, constraint
+from pyasn1.type import constraint
+from pyasn1.type import namedtype
+from pyasn1.type import tag
+from pyasn1.type import univ
 
 
 class ObjectName(univ.ObjectIdentifier):
diff --git a/pyasn1_modules/rfc1157.py b/pyasn1_modules/rfc1157.py
index 1ad1d27..9e6527b 100644
--- a/pyasn1_modules/rfc1157.py
+++ b/pyasn1_modules/rfc1157.py
@@ -12,7 +12,11 @@
 # Sample captures from:
 # http://wiki.wireshark.org/SampleCaptures/
 #
-from pyasn1.type import univ, namedtype, namedval, tag
+from pyasn1.type import namedtype
+from pyasn1.type import namedval
+from pyasn1.type import tag
+from pyasn1.type import univ
+
 from pyasn1_modules import rfc1155
 
 
diff --git a/pyasn1_modules/rfc1901.py b/pyasn1_modules/rfc1901.py
index eadf9aa..6e8d1f1 100644
--- a/pyasn1_modules/rfc1901.py
+++ b/pyasn1_modules/rfc1901.py
@@ -9,7 +9,9 @@
 # ASN.1 source from:
 # http://www.ietf.org/rfc/rfc1901.txt
 #
-from pyasn1.type import univ, namedtype, namedval
+from pyasn1.type import namedtype
+from pyasn1.type import namedval
+from pyasn1.type import univ
 
 
 class Message(univ.Sequence):
diff --git a/pyasn1_modules/rfc1902.py b/pyasn1_modules/rfc1902.py
index 5e9307e..7e815d2 100644
--- a/pyasn1_modules/rfc1902.py
+++ b/pyasn1_modules/rfc1902.py
@@ -9,7 +9,10 @@
 # ASN.1 source from:
 # http://www.ietf.org/rfc/rfc1902.txt
 #
-from pyasn1.type import univ, namedtype, tag, constraint
+from pyasn1.type import constraint
+from pyasn1.type import namedtype
+from pyasn1.type import tag
+from pyasn1.type import univ
 
 
 class Integer(univ.Integer):
diff --git a/pyasn1_modules/rfc1905.py b/pyasn1_modules/rfc1905.py
index de5bb03..31e4203 100644
--- a/pyasn1_modules/rfc1905.py
+++ b/pyasn1_modules/rfc1905.py
@@ -9,7 +9,12 @@
 # ASN.1 source from:
 # http://www.ietf.org/rfc/rfc1905.txt
 #
-from pyasn1.type import univ, namedtype, namedval, tag, constraint
+from pyasn1.type import constraint
+from pyasn1.type import namedtype
+from pyasn1.type import namedval
+from pyasn1.type import tag
+from pyasn1.type import univ
+
 from pyasn1_modules import rfc1902
 
 max_bindings = rfc1902.Integer(2147483647)
diff --git a/pyasn1_modules/rfc2251.py b/pyasn1_modules/rfc2251.py
index 94ba589..a4c07a0 100644
--- a/pyasn1_modules/rfc2251.py
+++ b/pyasn1_modules/rfc2251.py
@@ -12,7 +12,11 @@
 # Sample captures from:
 # http://wiki.wireshark.org/SampleCaptures/
 #
-from pyasn1.type import tag, namedtype, namedval, univ, constraint
+from pyasn1.type import constraint
+from pyasn1.type import namedtype
+from pyasn1.type import namedval
+from pyasn1.type import tag
+from pyasn1.type import univ
 
 maxInt = univ.Integer(2147483647)
 
diff --git a/pyasn1_modules/rfc2437.py b/pyasn1_modules/rfc2437.py
index 678d92d..4e4113f 100644
--- a/pyasn1_modules/rfc2437.py
+++ b/pyasn1_modules/rfc2437.py
@@ -11,7 +11,10 @@
 #
 # Sample captures could be obtained with "openssl genrsa" command
 #
-from pyasn1.type import tag, namedtype, univ
+from pyasn1.type import namedtype
+from pyasn1.type import tag
+from pyasn1.type import univ
+
 from pyasn1_modules.rfc2459 import AlgorithmIdentifier
 
 pkcs_1 = univ.ObjectIdentifier('1.2.840.113549.1.1')
diff --git a/pyasn1_modules/rfc2459.py b/pyasn1_modules/rfc2459.py
index 6855482..1f78185 100644
--- a/pyasn1_modules/rfc2459.py
+++ b/pyasn1_modules/rfc2459.py
@@ -13,7 +13,14 @@
 # Sample captures from:
 # http://wiki.wireshark.org/SampleCaptures/
 #
-from pyasn1.type import tag, namedtype, namedval, opentype, univ, constraint, char, useful
+from pyasn1.type import char
+from pyasn1.type import constraint
+from pyasn1.type import namedtype
+from pyasn1.type import namedval
+from pyasn1.type import opentype
+from pyasn1.type import tag
+from pyasn1.type import univ
+from pyasn1.type import useful
 
 MAX = float('inf')
 
diff --git a/pyasn1_modules/rfc2511.py b/pyasn1_modules/rfc2511.py
index 4ae7db5..b42d1d9 100644
--- a/pyasn1_modules/rfc2511.py
+++ b/pyasn1_modules/rfc2511.py
@@ -11,8 +11,8 @@
 #
 # Sample captures could be obtained with OpenSSL
 #
-from pyasn1_modules.rfc2459 import *
 from pyasn1_modules import rfc2315
+from pyasn1_modules.rfc2459 import *
 
 MAX = float('inf')
 
diff --git a/pyasn1_modules/rfc2560.py b/pyasn1_modules/rfc2560.py
index 472099e..47ca4e1 100644
--- a/pyasn1_modules/rfc2560.py
+++ b/pyasn1_modules/rfc2560.py
@@ -21,7 +21,12 @@
 # * dates are left as strings in GeneralizedTime format -- datetime.datetime
 # would be nicer
 #
-from pyasn1.type import tag, namedtype, namedval, univ, useful
+from pyasn1.type import namedtype
+from pyasn1.type import namedval
+from pyasn1.type import tag
+from pyasn1.type import univ
+from pyasn1.type import useful
+
 from pyasn1_modules import rfc2459
 
 
diff --git a/pyasn1_modules/rfc3279.py b/pyasn1_modules/rfc3279.py
index f69ff08..65a554d 100644
--- a/pyasn1_modules/rfc3279.py
+++ b/pyasn1_modules/rfc3279.py
@@ -6,7 +6,9 @@
 #
 # Derived from RFC 3279
 #
-from pyasn1.type import univ, char, namedtype, namedval, tag, constraint, useful
+from pyasn1.type import namedtype
+from pyasn1.type import namedval
+from pyasn1.type import univ
 
 
 def _OID(*components):
diff --git a/pyasn1_modules/rfc3280.py b/pyasn1_modules/rfc3280.py
index 3614e6c..f49dcfb 100644
--- a/pyasn1_modules/rfc3280.py
+++ b/pyasn1_modules/rfc3280.py
@@ -12,7 +12,13 @@
 # ASN.1 source from:
 # http://www.ietf.org/rfc/rfc3280.txt
 #
-from pyasn1.type import univ, char, namedtype, namedval, tag, constraint, useful
+from pyasn1.type import char
+from pyasn1.type import constraint
+from pyasn1.type import namedtype
+from pyasn1.type import namedval
+from pyasn1.type import tag
+from pyasn1.type import univ
+from pyasn1.type import useful
 
 MAX = float('inf')
 
diff --git a/pyasn1_modules/rfc3281.py b/pyasn1_modules/rfc3281.py
index 8aa99d3..9ecc2cd 100644
--- a/pyasn1_modules/rfc3281.py
+++ b/pyasn1_modules/rfc3281.py
@@ -11,12 +11,12 @@
 # ASN.1 source from:
 # http://www.ietf.org/rfc/rfc3281.txt
 #
-from pyasn1.type import univ
 from pyasn1.type import char
+from pyasn1.type import constraint
 from pyasn1.type import namedtype
 from pyasn1.type import namedval
 from pyasn1.type import tag
-from pyasn1.type import constraint
+from pyasn1.type import univ
 from pyasn1.type import useful
 
 from pyasn1_modules import rfc3280
diff --git a/pyasn1_modules/rfc3412.py b/pyasn1_modules/rfc3412.py
index b3f5a92..1492e62 100644
--- a/pyasn1_modules/rfc3412.py
+++ b/pyasn1_modules/rfc3412.py
@@ -9,7 +9,10 @@
 # ASN.1 source from:
 # http://www.ietf.org/rfc/rfc3412.txt
 #
-from pyasn1.type import univ, namedtype, constraint
+from pyasn1.type import constraint
+from pyasn1.type import namedtype
+from pyasn1.type import univ
+
 from pyasn1_modules import rfc1905
 
 
diff --git a/pyasn1_modules/rfc3414.py b/pyasn1_modules/rfc3414.py
index aeb82aa..cac18cf 100644
--- a/pyasn1_modules/rfc3414.py
+++ b/pyasn1_modules/rfc3414.py
@@ -9,7 +9,9 @@
 # ASN.1 source from:
 # http://www.ietf.org/rfc/rfc3414.txt
 #
-from pyasn1.type import univ, namedtype, constraint
+from pyasn1.type import constraint
+from pyasn1.type import namedtype
+from pyasn1.type import univ
 
 
 class UsmSecurityParameters(univ.Sequence):
diff --git a/pyasn1_modules/rfc3447.py b/pyasn1_modules/rfc3447.py
index 57c99fa..a2950aa 100644
--- a/pyasn1_modules/rfc3447.py
+++ b/pyasn1_modules/rfc3447.py
@@ -11,7 +11,9 @@
 #
 # Sample captures could be obtained with "openssl genrsa" command
 #
-from pyasn1.type import constraint, namedval
+from pyasn1.type import constraint
+from pyasn1.type import namedval
+
 from pyasn1_modules.rfc2437 import *
 
 
diff --git a/pyasn1_modules/rfc3852.py b/pyasn1_modules/rfc3852.py
index 872eb88..3b17fe5 100644
--- a/pyasn1_modules/rfc3852.py
+++ b/pyasn1_modules/rfc3852.py
@@ -11,7 +11,12 @@
 # ASN.1 source from:
 # http://www.ietf.org/rfc/rfc3852.txt
 #
-from pyasn1.type import univ, namedtype, namedval, tag, constraint, useful
+from pyasn1.type import constraint
+from pyasn1.type import namedtype
+from pyasn1.type import namedval
+from pyasn1.type import tag
+from pyasn1.type import univ
+from pyasn1.type import useful
 
 from pyasn1_modules import rfc3280
 from pyasn1_modules import rfc3281
diff --git a/pyasn1_modules/rfc4210.py b/pyasn1_modules/rfc4210.py
index d7e6db0..b93464f 100644
--- a/pyasn1_modules/rfc4210.py
+++ b/pyasn1_modules/rfc4210.py
@@ -8,8 +8,17 @@
 #
 # Based on Alex Railean's work
 #
-from pyasn1.type import tag, namedtype, namedval, univ, constraint, char, useful
-from pyasn1_modules import rfc2459, rfc2511, rfc2314
+from pyasn1.type import char
+from pyasn1.type import constraint
+from pyasn1.type import namedtype
+from pyasn1.type import namedval
+from pyasn1.type import tag
+from pyasn1.type import univ
+from pyasn1.type import useful
+
+from pyasn1_modules import rfc2314
+from pyasn1_modules import rfc2459
+from pyasn1_modules import rfc2511
 
 MAX = float('inf')
 
diff --git a/pyasn1_modules/rfc4211.py b/pyasn1_modules/rfc4211.py
index d20da78..9ff07f2 100644
--- a/pyasn1_modules/rfc4211.py
+++ b/pyasn1_modules/rfc4211.py
@@ -12,7 +12,12 @@
 # ASN.1 source from:
 # http://www.ietf.org/rfc/rfc4211.txt
 #
-from pyasn1.type import univ, char, namedtype, namedval, tag, constraint
+from pyasn1.type import char
+from pyasn1.type import constraint
+from pyasn1.type import namedtype
+from pyasn1.type import namedval
+from pyasn1.type import tag
+from pyasn1.type import univ
 
 from pyasn1_modules import rfc3280
 from pyasn1_modules import rfc3852
diff --git a/pyasn1_modules/rfc5208.py b/pyasn1_modules/rfc5208.py
index 6b6487d..7857d2f 100644
--- a/pyasn1_modules/rfc5208.py
+++ b/pyasn1_modules/rfc5208.py
@@ -11,8 +11,8 @@
 #
 # Sample captures could be obtained with "openssl pkcs8 -topk8" command
 #
-from pyasn1_modules.rfc2459 import *
 from pyasn1_modules import rfc2251
+from pyasn1_modules.rfc2459 import *
 
 
 class KeyEncryptionAlgorithms(AlgorithmIdentifier):
diff --git a/pyasn1_modules/rfc5280.py b/pyasn1_modules/rfc5280.py
index c750f28..2ecc627 100644
--- a/pyasn1_modules/rfc5280.py
+++ b/pyasn1_modules/rfc5280.py
@@ -12,17 +12,18 @@
 # ASN.1 source from:
 # http://www.ietf.org/rfc/rfc5280.txt
 #
-from pyasn1.type import univ
 from pyasn1.type import char
+from pyasn1.type import constraint
 from pyasn1.type import namedtype
 from pyasn1.type import namedval
 from pyasn1.type import opentype
 from pyasn1.type import tag
-from pyasn1.type import constraint
+from pyasn1.type import univ
 from pyasn1.type import useful
 
 MAX = float('inf')
 
+
 def _buildOid(*components):
     output = []
     for x in tuple(components):
diff --git a/pyasn1_modules/rfc6402.py b/pyasn1_modules/rfc6402.py
index c35f855..faee07f 100644
--- a/pyasn1_modules/rfc6402.py
+++ b/pyasn1_modules/rfc6402.py
@@ -11,7 +11,13 @@
 # ASN.1 source from:
 # http://www.ietf.org/rfc/rfc6402.txt
 #
-from pyasn1.type import univ, char, namedtype, namedval, tag, constraint, useful
+from pyasn1.type import char
+from pyasn1.type import constraint
+from pyasn1.type import namedtype
+from pyasn1.type import namedval
+from pyasn1.type import tag
+from pyasn1.type import univ
+from pyasn1.type import useful
 
 from pyasn1_modules import rfc4211
 from pyasn1_modules import rfc5280
diff --git a/tests/test_rfc2314.py b/tests/test_rfc2314.py
index 6dd5c47..9ff3176 100644
--- a/tests/test_rfc2314.py
+++ b/tests/test_rfc2314.py
@@ -5,13 +5,16 @@
 # License: http://pyasn1.sf.net/license.html
 #
 import sys
+
 from pyasn1.codec.der import decoder as der_decoder
 from pyasn1.codec.der import encoder as der_encoder
 
-from pyasn1_modules import rfc2314, pem
+from pyasn1_modules import pem
+from pyasn1_modules import rfc2314
 
 try:
     import unittest2 as unittest
+
 except ImportError:
     import unittest
 
diff --git a/tests/test_rfc2315.py b/tests/test_rfc2315.py
index 5dbdc4b..3a0c307 100644
--- a/tests/test_rfc2315.py
+++ b/tests/test_rfc2315.py
@@ -5,13 +5,16 @@
 # License: http://pyasn1.sf.net/license.html
 #
 import sys
+
 from pyasn1.codec.der import decoder as der_decoder
 from pyasn1.codec.der import encoder as der_encoder
 
-from pyasn1_modules import rfc2315, pem
+from pyasn1_modules import pem
+from pyasn1_modules import rfc2315
 
 try:
     import unittest2 as unittest
+
 except ImportError:
     import unittest
 
diff --git a/tests/test_rfc2437.py b/tests/test_rfc2437.py
index 8d3539a..748a9df 100644
--- a/tests/test_rfc2437.py
+++ b/tests/test_rfc2437.py
@@ -5,13 +5,16 @@
 # License: http://pyasn1.sf.net/license.html
 #
 import sys
+
 from pyasn1.codec.der import decoder as der_decoder
 from pyasn1.codec.der import encoder as der_encoder
 
-from pyasn1_modules import rfc2437, pem
+from pyasn1_modules import pem
+from pyasn1_modules import rfc2437
 
 try:
     import unittest2 as unittest
+
 except ImportError:
     import unittest
 
diff --git a/tests/test_rfc2459.py b/tests/test_rfc2459.py
index c3310d9..20a0d28 100644
--- a/tests/test_rfc2459.py
+++ b/tests/test_rfc2459.py
@@ -5,13 +5,16 @@
 # License: http://pyasn1.sf.net/license.html
 #
 import sys
+
 from pyasn1.codec.der import decoder as der_decoder
 from pyasn1.codec.der import encoder as der_encoder
 
-from pyasn1_modules import rfc2459, pem
+from pyasn1_modules import pem
+from pyasn1_modules import rfc2459
 
 try:
     import unittest2 as unittest
+
 except ImportError:
     import unittest
 
diff --git a/tests/test_rfc2511.py b/tests/test_rfc2511.py
index ef4cc00..cd5e266 100644
--- a/tests/test_rfc2511.py
+++ b/tests/test_rfc2511.py
@@ -5,13 +5,16 @@
 # License: http://pyasn1.sf.net/license.html
 #
 import sys
+
 from pyasn1.codec.der import decoder as der_decoder
 from pyasn1.codec.der import encoder as der_encoder
 
-from pyasn1_modules import rfc2511, pem
+from pyasn1_modules import pem
+from pyasn1_modules import rfc2511
 
 try:
     import unittest2 as unittest
+
 except ImportError:
     import unittest
 
diff --git a/tests/test_rfc2560.py b/tests/test_rfc2560.py
index 142284b..f96d36b 100644
--- a/tests/test_rfc2560.py
+++ b/tests/test_rfc2560.py
@@ -5,13 +5,16 @@
 # License: http://pyasn1.sf.net/license.html
 #
 import sys
+
 from pyasn1.codec.der import decoder as der_decoder
 from pyasn1.codec.der import encoder as der_encoder
 
-from pyasn1_modules import rfc2560, pem
+from pyasn1_modules import pem
+from pyasn1_modules import rfc2560
 
 try:
     import unittest2 as unittest
+
 except ImportError:
     import unittest
 
diff --git a/tests/test_rfc4210.py b/tests/test_rfc4210.py
index 35451c8..5c63c2e 100644
--- a/tests/test_rfc4210.py
+++ b/tests/test_rfc4210.py
@@ -5,13 +5,16 @@
 # License: http://pyasn1.sf.net/license.html
 #
 import sys
+
 from pyasn1.codec.der import decoder as der_decoder
 from pyasn1.codec.der import encoder as der_encoder
 
-from pyasn1_modules import rfc4210, pem
+from pyasn1_modules import pem
+from pyasn1_modules import rfc4210
 
 try:
     import unittest2 as unittest
+
 except ImportError:
     import unittest
 
diff --git a/tests/test_rfc5208.py b/tests/test_rfc5208.py
index 94d1d0e..285085d 100644
--- a/tests/test_rfc5208.py
+++ b/tests/test_rfc5208.py
@@ -5,13 +5,16 @@
 # License: http://pyasn1.sf.net/license.html
 #
 import sys
+
 from pyasn1.codec.der import decoder as der_decoder
 from pyasn1.codec.der import encoder as der_encoder
 
-from pyasn1_modules import rfc5208, pem
+from pyasn1_modules import pem
+from pyasn1_modules import rfc5208
 
 try:
     import unittest2 as unittest
+
 except ImportError:
     import unittest
 
diff --git a/tests/test_rfc5280.py b/tests/test_rfc5280.py
index 49983ef..852f4ca 100644
--- a/tests/test_rfc5280.py
+++ b/tests/test_rfc5280.py
@@ -5,13 +5,16 @@
 # License: http://pyasn1.sf.net/license.html
 #
 import sys
+
 from pyasn1.codec.der import decoder as der_decoder
 from pyasn1.codec.der import encoder as der_encoder
 
-from pyasn1_modules import rfc5280, pem
+from pyasn1_modules import pem
+from pyasn1_modules import rfc5280
 
 try:
     import unittest2 as unittest
+
 except ImportError:
     import unittest
 
diff --git a/tests/test_rfc5652.py b/tests/test_rfc5652.py
index 5fa4296..a2d1fc7 100644
--- a/tests/test_rfc5652.py
+++ b/tests/test_rfc5652.py
@@ -5,13 +5,17 @@
 # License: http://pyasn1.sf.net/license.html
 #
 import sys
+
 from pyasn1.codec.der import decoder as der_decoder
 from pyasn1.codec.der import encoder as der_encoder
 
-from pyasn1_modules import rfc5652, rfc6402, pem
+from pyasn1_modules import pem
+from pyasn1_modules import rfc5652
+from pyasn1_modules import rfc6402
 
 try:
     import unittest2 as unittest
+
 except ImportError:
     import unittest
 
diff --git a/tools/cmcdump.py b/tools/cmcdump.py
index bce48b1..d16774d 100755
--- a/tools/cmcdump.py
+++ b/tools/cmcdump.py
@@ -3,15 +3,20 @@
 # Read CMC certificate request with wrappers on stdin, parse each into
 # plain text, then build substrate from it
 #
-from pyasn1.codec.der import decoder, encoder
-from pyasn1_modules import rfc5652, rfc6402, pem
 import sys
 
+from pyasn1.codec.der import decoder
+from pyasn1.codec.der import encoder
+
+from pyasn1_modules import pem
+from pyasn1_modules import rfc5652
+from pyasn1_modules import rfc6402
+
 if len(sys.argv) != 1:
     print("""Usage:
 $ cat cmc_request.pem | %s""" % (sys.argv[0],))
     sys.exit(-1)
-    
+
 reqCnt = 0
 
 substrate = pem.readBase64FromFile(sys.stdin)
@@ -26,7 +31,7 @@
         layer, rest = decoder.decode(data, asn1Spec=rfc5652.ContentInfo())
         assert encoder.encode(layer) == data, 'wrapper recode fails'
         assert not rest
-    
+
         print(" * New layer (wrapper):")
         print(layer.prettyPrint())
 
diff --git a/tools/cmpdump.py b/tools/cmpdump.py
index c89951a..ee8092b 100755
--- a/tools/cmpdump.py
+++ b/tools/cmpdump.py
@@ -8,24 +8,28 @@
 # Read ASN.1/PEM CMP message on stdin, parse into
 # plain text, then build substrate from it
 #
-from pyasn1.codec.der import decoder, encoder
-from pyasn1_modules import rfc4210, pem
-from pyasn1 import debug
 import sys
 
+from pyasn1 import debug
+from pyasn1.codec.der import decoder
+from pyasn1.codec.der import encoder
+
+from pyasn1_modules import pem
+from pyasn1_modules import rfc4210
+
 if len(sys.argv) == 2 and sys.argv[1] == '-d':
     debug.setLogger(debug.Debug('all'))
 elif len(sys.argv) != 1:
     print("""Usage:
 $ cat cmp.pem | %s [-d]""" % sys.argv[0])
     sys.exit(-1)
-    
+
 pkiMessage = rfc4210.PKIMessage()
 
 substrate = pem.readBase64FromFile(sys.stdin)
 if not substrate:
     sys.exit(0)
-        
+
 pkiMsg, rest = decoder.decode(substrate, asn1Spec=pkiMessage)
 
 print(pkiMsg.prettyPrint())
diff --git a/tools/crldump.py b/tools/crldump.py
index b871ddd..9731129 100755
--- a/tools/crldump.py
+++ b/tools/crldump.py
@@ -9,10 +9,14 @@
 # original wire format.
 # CRL can be generated with "openssl openssl ca -gencrl ..." commands.
 #
-from pyasn1_modules import rfc2459, pem
-from pyasn1.codec.der import encoder, decoder
 import sys
 
+from pyasn1.codec.der import decoder
+from pyasn1.codec.der import encoder
+
+from pyasn1_modules import pem
+from pyasn1_modules import rfc2459
+
 if len(sys.argv) != 1:
     print("""Usage:
 $ cat crl.pem | %s""" % sys.argv[0])
diff --git a/tools/crmfdump.py b/tools/crmfdump.py
index efb0ffc..854bfec 100755
--- a/tools/crmfdump.py
+++ b/tools/crmfdump.py
@@ -8,21 +8,25 @@
 # Read ASN.1/PEM X.509 CRMF request on stdin, parse into
 # plain text, then build substrate from it
 #
-from pyasn1.codec.der import decoder, encoder
-from pyasn1_modules import rfc2511, pem
 import sys
 
+from pyasn1.codec.der import decoder
+from pyasn1.codec.der import encoder
+
+from pyasn1_modules import pem
+from pyasn1_modules import rfc2511
+
 if len(sys.argv) != 1:
     print("""Usage:
 $ cat crmf.pem | %s""" % sys.argv[0])
     sys.exit(-1)
-    
+
 certReq = rfc2511.CertReqMessages()
 
 substrate = pem.readBase64FromFile(sys.stdin)
 if not substrate:
     sys.exit(0)
-        
+
 cr, rest = decoder.decode(substrate, asn1Spec=certReq)
 
 print(cr.prettyPrint())
diff --git a/tools/ocspclient.py b/tools/ocspclient.py
index 07ff5ad..2827604 100755
--- a/tools/ocspclient.py
+++ b/tools/ocspclient.py
@@ -10,13 +10,17 @@
 
 try:
     import urllib2
+
 except ImportError:
     import urllib.request as urllib2
 
-from pyasn1.codec.der import decoder, encoder
+from pyasn1.codec.der import decoder
+from pyasn1.codec.der import encoder
 from pyasn1.type import univ
 
-from pyasn1_modules import rfc2560, rfc2459, pem
+from pyasn1_modules import rfc2560
+from pyasn1_modules import rfc2459
+from pyasn1_modules import pem
 
 sha1oid = univ.ObjectIdentifier((1, 3, 14, 3, 2, 26))
 
diff --git a/tools/ocspreqdump.py b/tools/ocspreqdump.py
index 40c088a..f613f3a 100755
--- a/tools/ocspreqdump.py
+++ b/tools/ocspreqdump.py
@@ -8,10 +8,14 @@
 # Read ASN.1/PEM X.509 CRMF request on stdin, parse into
 # plain text, then build substrate from it
 #
-from pyasn1.codec.der import decoder, encoder
-from pyasn1_modules import rfc2560, pem
 import sys
 
+from pyasn1.codec.der import decoder
+from pyasn1.codec.der import encoder
+
+from pyasn1_modules import pem
+from pyasn1_modules import rfc2560
+
 if len(sys.argv) != 1:
     print("""Usage:
 $ cat ocsp-request.pem | %s""" % sys.argv[0])
diff --git a/tools/ocsprspdump.py b/tools/ocsprspdump.py
index ca52f64..3535795 100755
--- a/tools/ocsprspdump.py
+++ b/tools/ocsprspdump.py
@@ -8,10 +8,14 @@
 # Read ASN.1/PEM OCSP response on stdin, parse into
 # plain text, then build substrate from it
 #
-from pyasn1.codec.der import decoder, encoder
-from pyasn1_modules import rfc2560, pem
 import sys
 
+from pyasn1.codec.der import decoder
+from pyasn1.codec.der import encoder
+
+from pyasn1_modules import pem
+from pyasn1_modules import rfc2560
+
 if len(sys.argv) != 1:
     print("""Usage:
 $ cat ocsp-response.pem | %s""" % sys.argv[0])
diff --git a/tools/pkcs10dump.py b/tools/pkcs10dump.py
index 56417ae..e8c6da5 100755
--- a/tools/pkcs10dump.py
+++ b/tools/pkcs10dump.py
@@ -8,10 +8,14 @@
 # Read ASN.1/PEM X.509 certificate requests (PKCS#10 format) on stdin, 
 # parse each into plain text, then build substrate from it
 #
-from pyasn1.codec.der import decoder, encoder
-from pyasn1_modules import rfc2314, pem
 import sys
 
+from pyasn1.codec.der import decoder
+from pyasn1.codec.der import encoder
+
+from pyasn1_modules import pem
+from pyasn1_modules import rfc2314
+
 if len(sys.argv) != 1:
     print("""Usage:
 $ cat certificateRequest.pem | %s""" % sys.argv[0])
diff --git a/tools/pkcs1dump.py b/tools/pkcs1dump.py
index f205d77..520fc4c 100755
--- a/tools/pkcs1dump.py
+++ b/tools/pkcs1dump.py
@@ -9,10 +9,15 @@
 # stdin, print them pretty and encode back into original wire format.
 # Private keys can be generated with "openssl genrsa|gendsa" commands.
 #
-from pyasn1_modules import rfc2459, rfc2437, pem
-from pyasn1.codec.der import encoder, decoder
 import sys
 
+from pyasn1.codec.der import decoder
+from pyasn1.codec.der import encoder
+
+from pyasn1_modules import pem
+from pyasn1_modules import rfc2437
+from pyasn1_modules import rfc2459
+
 if len(sys.argv) != 1:
     print("""Usage:
 $ cat rsakey.pem | %s""" % sys.argv[0])
diff --git a/tools/pkcs7dump.py b/tools/pkcs7dump.py
index 72fe70d..c01e19c 100755
--- a/tools/pkcs7dump.py
+++ b/tools/pkcs7dump.py
@@ -8,10 +8,14 @@
 # Read ASN.1/PEM PKCS#7 on stdin, parse it into plain text,
 # then build substrate from it
 #
-from pyasn1_modules import rfc2315, pem
-from pyasn1.codec.der import encoder, decoder
 import sys
 
+from pyasn1.codec.der import decoder
+from pyasn1.codec.der import encoder
+
+from pyasn1_modules import pem
+from pyasn1_modules import rfc2315
+
 if len(sys.argv) != 1:
     print("""Usage:
 $ cat pkcs7Certificate.pem | %s""" % sys.argv[0])
diff --git a/tools/pkcs8dump.py b/tools/pkcs8dump.py
index 2bb8388..d645a87 100755
--- a/tools/pkcs8dump.py
+++ b/tools/pkcs8dump.py
@@ -8,10 +8,14 @@
 # Read  bunch of ASN.1/PEM plain/encrypted private keys in PKCS#8 
 # format on stdin, parse each into plain text, then build substrate from it
 #
-from pyasn1.codec.der import decoder, encoder
-from pyasn1_modules import rfc5208, pem
 import sys
 
+from pyasn1.codec.der import decoder
+from pyasn1.codec.der import encoder
+
+from pyasn1_modules import pem
+from pyasn1_modules import rfc5208
+
 if len(sys.argv) != 1:
     print("""Usage:
 $ cat pkcs8key.pem | %s""" % sys.argv[0])
diff --git a/tools/snmpget.py b/tools/snmpget.py
index cd9fec2..877d521 100755
--- a/tools/snmpget.py
+++ b/tools/snmpget.py
@@ -7,10 +7,13 @@
 #
 # Generate SNMPGET request, parse response
 #
-from pyasn1.codec.ber import encoder, decoder
-from pyasn1_modules import rfc1157
-import sys
 import socket
+import sys
+
+from pyasn1.codec.ber import decoder
+from pyasn1.codec.ber import encoder
+
+from pyasn1_modules import rfc1157
 
 if len(sys.argv) != 4:
     print("""Usage:
diff --git a/tools/x509dump-rfc5280.py b/tools/x509dump-rfc5280.py
index 482df7e..d1ae38b 100755
--- a/tools/x509dump-rfc5280.py
+++ b/tools/x509dump-rfc5280.py
@@ -10,10 +10,14 @@
 # Read ASN.1/PEM X.509 certificates on stdin, parse each into plain text,
 # then build substrate from it (using RFC5280)
 #
-from pyasn1.codec.der import decoder, encoder
-from pyasn1_modules import rfc5280, pem
 import sys
 
+from pyasn1.codec.der import decoder
+from pyasn1.codec.der import encoder
+
+from pyasn1_modules import pem
+from pyasn1_modules import rfc5280
+
 if len(sys.argv) != 1:
     print("""Usage:
 $ cat CACertificate.pem | %s
diff --git a/tools/x509dump.py b/tools/x509dump.py
index 2c51c6a..5a36915 100755
--- a/tools/x509dump.py
+++ b/tools/x509dump.py
@@ -8,10 +8,14 @@
 # Read ASN.1/PEM X.509 certificates on stdin, parse each into plain text,
 # then build substrate from it
 #
-from pyasn1.codec.der import decoder, encoder
-from pyasn1_modules import rfc2459, pem
 import sys
 
+from pyasn1.codec.der import decoder
+from pyasn1.codec.der import encoder
+
+from pyasn1_modules import pem
+from pyasn1_modules import rfc2459
+
 if len(sys.argv) != 1:
     print("""Usage:
 $ cat CACertificate.pem | %s