diff --git a/migrate/changeset/ansisql.py b/migrate/changeset/ansisql.py
index f80c38a..39fb261 100644
--- a/migrate/changeset/ansisql.py
+++ b/migrate/changeset/ansisql.py
@@ -99,7 +99,8 @@ class ANSIColumnGenerator(AlterTableVisitor, SchemaGenerator):
                        unique=bool(column.index_name or column.index))
             ix.create()
         elif column.unique_name:
-            constraint.UniqueConstraint(column, name=column.unique_name).create()
+            constraint.UniqueConstraint(column,
+                                        name=column.unique_name).create()
 
         # SA bounds FK constraints to table, add manually
         for fk in column.foreign_keys:
@@ -107,7 +108,8 @@ class ANSIColumnGenerator(AlterTableVisitor, SchemaGenerator):
 
         # add primary key constraint if needed
         if column.primary_key_name:
-            cons = constraint.PrimaryKeyConstraint(column, name=column.primary_key_name)
+            cons = constraint.PrimaryKeyConstraint(column,
+                                                   name=column.primary_key_name)
             cons.create()
 
 
@@ -145,14 +147,17 @@ class ANSISchemaChanger(AlterTableVisitor, SchemaGenerator):
     def visit_table(self, table):
         """Rename a table. Other ops aren't supported."""
         self.start_alter_table(table)
-        self.append("RENAME TO %s" % self.preparer.quote(table.new_name, table.quote))
+        self.append("RENAME TO %s" % self.preparer.quote(table.new_name,
+                                                         table.quote))
         self.execute()
 
     def visit_index(self, index):
         """Rename an index"""
         self.append("ALTER INDEX %s RENAME TO %s" %
-            (self.preparer.quote(self._validate_identifier(index.name, True), index.quote),
-             self.preparer.quote(self._validate_identifier(index.new_name, True) , index.quote)))
+            (self.preparer.quote(self._validate_identifier(index.name,
+                                                           True), index.quote),
+             self.preparer.quote(self._validate_identifier(index.new_name,
+                                                           True), index.quote)))
         self.execute()
 
     def visit_column(self, column):
diff --git a/migrate/changeset/databases/__init__.py b/migrate/changeset/databases/__init__.py
index 4abc187..8546918 100644
--- a/migrate/changeset/databases/__init__.py
+++ b/migrate/changeset/databases/__init__.py
@@ -2,7 +2,7 @@
    This module contains database dialect specific changeset
    implementations.
 """
-__all__=[
+__all__ = [
     'postgres',
     'sqlite',
     'mysql',
diff --git a/migrate/changeset/databases/oracle.py b/migrate/changeset/databases/oracle.py
index abdaad8..59e266e 100644
--- a/migrate/changeset/databases/oracle.py
+++ b/migrate/changeset/databases/oracle.py
@@ -42,16 +42,14 @@ class OracleSchemaChanger(OracleSchemaGenerator, ansisql.ANSISchemaChanger):
 
     def _visit_column_change(self, table, col_name, delta):
         if not hasattr(delta, 'result_column'):
-            # Oracle needs the whole column definition, not just a
-            # lone name/type
+            # Oracle needs the whole column definition, not just a lone name/type
             raise exceptions.NotSupportedError(
                 "A column object is required to do this")
 
         column = delta.result_column
         # Oracle cannot drop a default once created, but it can set it
         # to null.  We'll do that if default=None
-        # http://forums.oracle.com/forums/message.jspa?\
-        # messageID=1273234#1273234
+        # http://forums.oracle.com/forums/message.jspa?messageID=1273234#1273234
         dropdefault_hack = (column.server_default is None \
                                 and 'server_default' in delta.keys())
         # Oracle apparently doesn't like it when we say "not null" if
diff --git a/migrate/changeset/databases/visitor.py b/migrate/changeset/databases/visitor.py
index 2f282c7..8a084fb 100644
--- a/migrate/changeset/databases/visitor.py
+++ b/migrate/changeset/databases/visitor.py
@@ -8,7 +8,7 @@ from migrate.changeset.databases import sqlite, postgres, mysql, oracle
 
 
 # Map SA dialects to the corresponding Migrate extensions
-dialects = {
+DIALECTS = {
     sa.engine.default.DefaultDialect: ansisql.ANSIDialect,
     sa.databases.sqlite.SQLiteDialect: sqlite.SQLiteDialect,
     sa.databases.postgres.PGDialect: postgres.PGDialect,
@@ -43,7 +43,7 @@ def get_dialect_visitor(sa_dialect, name):
 
     # map sa dialect to migrate dialect and return visitor
     sa_dialect_cls = sa_dialect.__class__
-    migrate_dialect_cls = dialects[sa_dialect_cls]
+    migrate_dialect_cls = DIALECTS[sa_dialect_cls]
     visitor = getattr(migrate_dialect_cls, name)
 
     # bind preparer
diff --git a/migrate/versioning/api.py b/migrate/versioning/api.py
index d72d14e..6e0da11 100644
--- a/migrate/versioning/api.py
+++ b/migrate/versioning/api.py
@@ -2,11 +2,13 @@
    This module provides an external API to the versioning system.
 
    .. versionchanged:: 0.4.5 
-    ``--preview_sql`` displays source file when using SQL scripts. If Python script is used,
-    it runs the action with mocked engine and returns captured SQL statements.
+    ``--preview_sql`` displays source file when using SQL scripts.
+    If Python script is used, it runs the action with mocked engine and
+    returns captured SQL statements.
 
    .. versionchanged:: 0.4.5
-    Deprecated ``--echo`` parameter in favour of new :func:`migrate.versioning.util.construct_engine` behavior.
+    Deprecated ``--echo`` parameter in favour of new
+    :func:`migrate.versioning.util.construct_engine` behavior.
 """
 
 # Dear migrate developers,
diff --git a/migrate/versioning/base/__init__.py b/migrate/versioning/base/__init__.py
index 1c803d9..4c3842a 100644
--- a/migrate/versioning/base/__init__.py
+++ b/migrate/versioning/base/__init__.py
@@ -1,5 +1,5 @@
 """Things that should be imported by all migrate packages"""
 
 #__all__ = ['logging','log','databases','operations']
-from logger import logging,log
-from const import databases,operations
+from logger import logging, log
+from const import databases, operations
diff --git a/migrate/versioning/base/const.py b/migrate/versioning/base/const.py
index 21271dd..590f6c0 100644
--- a/migrate/versioning/base/const.py
+++ b/migrate/versioning/base/const.py
@@ -1,10 +1,11 @@
-__all__ = ['databases','operations']
+from sqlalchemy.util import OrderedDict
 
-#databases = ('sqlite','postgres','mysql','oracle','mssql','firebird')
-databases = ('sqlite','postgres','mysql','oracle','mssql')
+
+__all__ = ['databases', 'operations']
+
+databases = ('sqlite', 'postgres', 'mysql', 'oracle', 'mssql')
 
 # Map operation names to function names
-from sqlalchemy.util import OrderedDict
 operations = OrderedDict()
 operations['upgrade'] = 'upgrade'
 operations['downgrade'] = 'downgrade'
diff --git a/migrate/versioning/base/logger.py b/migrate/versioning/base/logger.py
index 9cd3e59..0f97d40 100644
--- a/migrate/versioning/base/logger.py
+++ b/migrate/versioning/base/logger.py
@@ -6,4 +6,4 @@ log=logging.getLogger('migrate.versioning')
 log.setLevel(logging.WARNING)
 log.addHandler(logging.StreamHandler())
 
-__all__=['log','logging']
+__all__ = ['log','logging']
diff --git a/migrate/versioning/pathed.py b/migrate/versioning/pathed.py
index 2355486..6174737 100644
--- a/migrate/versioning/pathed.py
+++ b/migrate/versioning/pathed.py
@@ -52,7 +52,7 @@ class Pathed(KeyedInstance):
         #
         # Treat directories like files...
         if path[-1] == '/':
-            path=path[:-1]
+            path = path[:-1]
         ret = os.path.dirname(path)
         return ret
 
diff --git a/migrate/versioning/schema.py b/migrate/versioning/schema.py
index 9b71ba7..5227ccc 100644
--- a/migrate/versioning/schema.py
+++ b/migrate/versioning/schema.py
@@ -62,7 +62,9 @@ class ControlledSchema(object):
     def changeset(self, version=None):
         """API to Changeset creation.
         
-        Uses self.version for start version and engine.name to get database name."""
+        Uses self.version for start version and engine.name
+        to get database name.
+        """
         database = self.engine.name
         start_ver = self.version
         changeset = self.repository.changeset(database, start_ver, version)
diff --git a/migrate/versioning/script/py.py b/migrate/versioning/script/py.py
index c08d438..6a089ee 100644
--- a/migrate/versioning/script/py.py
+++ b/migrate/versioning/script/py.py
@@ -112,7 +112,7 @@ class PythonScript(base.BaseScript):
         """
         buf = StringIO()
         args['engine_arg_strategy'] = 'mock'
-        args['engine_arg_executor'] = lambda s, p='': buf.write(s + p)
+        args['engine_arg_executor'] = lambda s, p = '': buf.write(s + p)
         engine = construct_engine(url, **args)
 
         self.run(engine, step)
diff --git a/migrate/versioning/shell.py b/migrate/versioning/shell.py
index 2489f6b..3fa1478 100644
--- a/migrate/versioning/shell.py
+++ b/migrate/versioning/shell.py
@@ -17,8 +17,8 @@ alias = dict(
 
 def alias_setup():
     global alias
-    for key,val in alias.iteritems():
-        setattr(api,key,val)
+    for key, val in alias.iteritems():
+        setattr(api, key, val)
 alias_setup()
 
 
@@ -33,7 +33,8 @@ class PassiveOptionParser(OptionParser):
                 del rargs[0]
                 return
             elif arg[0:2] == "--":
-                # if parser does not know about the option, pass it along (make it anonymous)
+                # if parser does not know about the option
+                # pass it along (make it anonymous)
                 try:
                     opt = arg.split('=', 1)[0]
                     self._match_long_opt(opt)
@@ -49,13 +50,15 @@ class PassiveOptionParser(OptionParser):
                 del rargs[0]
 
 def main(argv=None, **kwargs):
-    """kwargs are default options that can be overriden with passing --some_option to cmdline"""
+    """kwargs are default options that can be overriden with passing
+    --some_option to cmdline
+    """
 
     argv = argv or list(sys.argv[1:])
     commands = list(api.__all__)
     commands.sort()
 
-    usage="""%%prog COMMAND ...
+    usage = """%%prog COMMAND ...
 
     Available commands:
         %s
@@ -129,7 +132,8 @@ def main(argv=None, **kwargs):
         try:
             kw = f_required.pop(0)
         except IndexError:
-            parser.error("Too many arguments for command %s: %s" % (command, arg))
+            parser.error("Too many arguments for command %s: %s" % (command,
+                                                                    arg))
         kwargs[kw] = arg
 
     # apply overrides
@@ -143,7 +147,8 @@ def main(argv=None, **kwargs):
     f_args_default = f_args[len(f_args) - num_defaults:]
     required = list(set(f_required) - set(f_args_default))
     if required:
-        parser.error("Not enough arguments for command %s: %s not specified" % (command, ', '.join(required)))
+        parser.error("Not enough arguments for command %s: %s not specified" \
+            % (command, ', '.join(required)))
 
     # handle command
     try:
diff --git a/migrate/versioning/template.py b/migrate/versioning/template.py
index f20d391..91606a7 100644
--- a/migrate/versioning/template.py
+++ b/migrate/versioning/template.py
@@ -24,6 +24,7 @@ class Packaged(pathed.Pathed):
         ret = resource_filename(pkg_name, resource_name)
         return ret
 
+
 class Collection(Packaged):
     """A collection of templates of a specific type"""
 
@@ -35,12 +36,15 @@ class Collection(Packaged):
     def get_pkg(self, file):
         return (self.pkg, str(file))
 
+
 class RepositoryCollection(Collection):
     _default = 'default'
 
+
 class ScriptCollection(Collection):
     _default = 'default.py_tmpl'
 
+
 class Template(Packaged):
     """Finds the paths/packages of various Migrate templates"""
 
@@ -50,8 +54,9 @@ class Template(Packaged):
 
     def __init__(self, pkg):
         super(Template, self).__init__(pkg)
-        self.repository=RepositoryCollection('.'.join((self.pkg, self._repository)))
-        self.script=ScriptCollection('.'.join((self.pkg, self._script)))
+        self.repository = RepositoryCollection('.'.join((self.pkg,
+                                                         self._repository)))
+        self.script = ScriptCollection('.'.join((self.pkg, self._script)))
 
     def get_item(self, attr, filename=None, as_pkg=None, as_str=None):
         item = getattr(self, attr)
@@ -74,5 +79,6 @@ class Template(Packaged):
     def manage(self, **k):
         return (self.pkg, self._manage)
 
+
 template_pkg = 'migrate.versioning.templates'
 template = Template(template_pkg)
diff --git a/migrate/versioning/version.py b/migrate/versioning/version.py
index ab457ab..18dc00a 100644
--- a/migrate/versioning/version.py
+++ b/migrate/versioning/version.py
@@ -161,7 +161,8 @@ class Version(object):
         # TODO: maybe add force Python parameter?
         ret = self.python
 
-        assert ret is not None, "There is no script for %d version" % self.version
+        assert ret is not None,
+            "There is no script for %d version" % self.version
         return ret
 
     # deprecated?