Fix documentation bug

Fixes: https://github.com/bazelbuild/rules_python/issues/7
diff --git a/README.md b/README.md
index 8daf912..76791a7 100644
--- a/README.md
+++ b/README.md
@@ -28,7 +28,7 @@
 )
 
 # Only needed for PIP support:
-load("//python:pip.bzl", "pip_repositories")
+load("@io_bazel_rules_python//python:pip.bzl", "pip_repositories")
 
 pip_repositories()
 ```