diff --git a/graphene_sqlalchemy/converter.py b/graphene_sqlalchemy/converter.py
index 17e54b0f..2543fc84 100644
--- a/graphene_sqlalchemy/converter.py
+++ b/graphene_sqlalchemy/converter.py
@@ -10,16 +10,10 @@
 from .fields import createConnectionField
 
 try:
-    from sqlalchemy_utils import ChoiceType, JSONType, ScalarListType, TSVectorType
+    from sqlalchemy_utils import (
+        ChoiceType, JSONType, ScalarListType, TSVectorType)
 except ImportError:
-    class ChoiceType(object):
-        pass
-
-    class ScalarListType(object):
-        pass
-
-    class JSONType(object):
-        pass
+    ChoiceType = JSONType = ScalarListType = TSVectorType = object
 
 
 def get_column_doc(column):
@@ -38,10 +32,9 @@ def dynamic_type():
         _type = registry.get_type_for_model(model)
         if not _type:
             return None
-        if (direction == interfaces.MANYTOONE or not relationship.uselist):
+        if direction == interfaces.MANYTOONE or not relationship.uselist:
             return Field(_type)
-        elif (direction == interfaces.ONETOMANY or
-              direction == interfaces.MANYTOMANY):
+        elif direction in (interfaces.ONETOMANY, interfaces.MANYTOMANY):
             if _type._meta.connection:
                 return createConnectionField(_type)
             return Field(List(_type))
diff --git a/graphene_sqlalchemy/types.py b/graphene_sqlalchemy/types.py
index 44bf9c27..04d1a8a6 100644
--- a/graphene_sqlalchemy/types.py
+++ b/graphene_sqlalchemy/types.py
@@ -28,7 +28,7 @@ def construct_fields(model, registry, only_fields, exclude_fields):
         is_excluded = name in exclude_fields  # or is_already_created
         if is_not_in_only or is_excluded:
             # We skip this field if we specify only_fields and is not
-            # in there. Or when we excldue this field in exclude_fields
+            # in there. Or when we exclude this field in exclude_fields
             continue
         converted_column = convert_sqlalchemy_column(column, registry)
         fields[name] = converted_column
@@ -39,7 +39,7 @@ def construct_fields(model, registry, only_fields, exclude_fields):
         is_excluded = name in exclude_fields  # or is_already_created
         if is_not_in_only or is_excluded:
             # We skip this field if we specify only_fields and is not
-            # in there. Or when we excldue this field in exclude_fields
+            # in there. Or when we exclude this field in exclude_fields
             continue
         converted_composite = convert_sqlalchemy_composite(composite, registry)
         fields[name] = converted_composite
@@ -55,7 +55,7 @@ def construct_fields(model, registry, only_fields, exclude_fields):
 
             if is_not_in_only or is_excluded:
                 # We skip this field if we specify only_fields and is not
-                # in there. Or when we excldue this field in exclude_fields
+                # in there. Or when we exclude this field in exclude_fields
                 continue
 
             converted_hybrid_property = convert_sqlalchemy_hybrid_method(
@@ -70,7 +70,7 @@ def construct_fields(model, registry, only_fields, exclude_fields):
         is_excluded = relationship.key in exclude_fields  # or is_already_created
         if is_not_in_only or is_excluded:
             # We skip this field if we specify only_fields and is not
-            # in there. Or when we excldue this field in exclude_fields
+            # in there. Or when we exclude this field in exclude_fields
             continue
         converted_relationship = convert_sqlalchemy_relationship(relationship, registry)
         name = relationship.key