Fix for graphql-python#21 and graphql-python#22.

Author: miracle2k

graphql/core/execution/values.py

@@ -128,7 +128,7 @@ def coerce_value(type, value):
         fields = type.get_fields()
         obj = {}
         for field_name, field in fields.items():
-            field_value = coerce_value(field.type, value[field_name])
+            field_value = coerce_value(field.type, value.get(field_name))
             if field_value is None:
                 field_value = field.default_value
 

graphql/core/type/scalars.py

@@ -62,7 +62,7 @@ def parse_float_literal(ast):
 def coerce_string(value):
     if isinstance(value, bool):
         return 'true' if value else 'false'
-    return str(value)
+    return unicode(value)
 
 
 def parse_string_literal(ast):