Removed Unnecessary default_value=Undefined in ast

Author: syrusakbary

graphql/language/ast.py

@@ -1,6 +1,5 @@
 # This is autogenerated code. DO NOT change this manually.
 # Run scripts/generate_ast.py to generate this file.
-from ..utils.undefined import Undefined
 
 
 class Node(object):
@@ -95,7 +94,7 @@ class VariableDefinition(Node):
     __slots__ = ('loc', 'variable', 'type', 'default_value',)
     _fields = ('variable', 'type', 'default_value',)
 
-    def __init__(self, variable, type, default_value=Undefined, loc=None):
+    def __init__(self, variable, type, default_value=None, loc=None):
         self.loc = loc
         self.variable = variable
         self.type = type
@@ -1006,7 +1005,7 @@ class InputValueDefinition(Node):
     __slots__ = ('loc', 'name', 'type', 'default_value', 'directives')
     _fields = ('name', 'type', 'default_value',)
 
-    def __init__(self, name, type, default_value=Undefined, loc=None,
+    def __init__(self, name, type, default_value=None, loc=None,
                  directives=None):
         self.loc = loc
         self.name = name