class_docstr: Checker used for enum fields.  Performs type-check and range check.
code: def __init__(self, enum_type):
      self._enum_type = enum_type
  
imports: import numbers
  import six
  from google.protobuf.internal import api_implementation
  from google.protobuf.internal import decoder
  from google.protobuf.internal import encoder
  from google.protobuf.internal import wire_format
  from google.protobuf import descriptor
label_desc: Use image node_id 1 to create a new EnumValueChecker object from inherited base classes: object with example: obj = EnumValueChecker(enum_type)