def decode_map(self, data_type, obj):
if not isinstance(obj, dict):<EOL><INDENT>raise bv.ValidationError(<EOL>'<STR_LIT>' % bv.generic_type_name(obj))<EOL><DEDENT>return {<EOL>self.json_compat_obj_decode_helper(data_type.key_validator, key):<EOL>self.json_compat_obj_decode_helper(data_type.value_validator, value)<EOL>for key, value in obj.items()<EOL>}<EOL>
The data_type argument must be a Map.
See json_compat_obj_decode() for argument descriptions.