Fix a copypasto bug. Also rename the parameter in question to not shadow the
'file' builtin, and fix up a docstring a little.

Hat tip to Sebastian Kreft Carreno at Google for noticing the bug.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@169887 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/bindings/python/clang/cindex.py b/bindings/python/clang/cindex.py
index 5e162c0..adbf511 100644
--- a/bindings/python/clang/cindex.py
+++ b/bindings/python/clang/cindex.py
@@ -3046,13 +3046,13 @@
         Config.library_path = path
 
     @staticmethod
-    def set_library_file(file):
-        """Set the exact location of libclang from"""
+    def set_library_file(filename):
+        """Set the exact location of libclang"""
         if Config.loaded:
             raise Exception("library file must be set before before using " \
                             "any other functionalities in libclang.")
 
-        Config.library_file = path
+        Config.library_file = filename
 
     @staticmethod
     def set_compatibility_check(check_status):