py34 and py27 compat

web3/utils/caching.py

@@ -1,5 +1,4 @@
 import hashlib
-import collections
 
 from .types import (
     is_boolean,
@@ -13,6 +12,9 @@ from .types import (
 from .string import (
     force_bytes,
 )
+from .compat import (
+    Generator,
+)
 
 
 def generate_cache_key(value):
@@ -31,7 +33,7 @@ def generate_cache_key(value):
             for key
             in sorted(value.keys())
         ))
-    elif is_array(value) or isinstance(value, collections.Generator):
+    elif is_array(value) or isinstance(value, Generator):
         return generate_cache_key("".join((
             generate_cache_key(item)
             for item

web3/utils/compat/__init__.py

@@ -6,11 +6,13 @@ if sys.version_info.major == 2:
     from .compat_py2 import (
         urlparse,
         urlunparse,
+        Generator,
     )
 else:
     from .compat_py3 import (  # noqa: #401
         urlparse,
         urlunparse,
+        Generator,
     )
 
 

web3/utils/compat/compat_py2.py

@@ -2,3 +2,4 @@ from urlparse import (  # noqa: F401
     urlparse,
     urlunparse,
 )
+Generator = type(_ for _ in tuple())

web3/utils/compat/compat_py3.py

@@ -1,4 +1,8 @@
+import collections
+
 from urllib.parse import (  # noqa: F401
     urlparse,
     urlunparse,
 )
+
+Generator = collections.Generator