class_docstr: A type used to describe a single field in the schema:
  
  - name: name of the field.
  - numpy_dtype: a numpy ``dtype`` reference
  - shape: shape of the multidimensional array. None value is used to define a dimension with variable number of
           elements. E.g. ``(None, 3)`` defines a point cloud with three coordinates but unknown number of points.
  - codec: An instance of a codec object used to encode/decode data during serialization
           (e.g. ``CompressedImageCodec('png')``)
  - nullable: Boolean indicating whether field can be None
  
  A field is considered immutable, so we override both equality and hash operators for consistency
  and efficiency.
code: def __ne__(self, other):
      return not self.__eq__(other)
  
imports: import copy
  import re
  import sys
  import warnings
  from collections import namedtuple, OrderedDict
  from decimal import Decimal
  from typing import Dict, Any, Tuple, Optional, NamedTuple
  import numpy
  import pyarrow
  import six
  from pyarrow.lib import ListType
  from pyarrow.lib import StructType
  from six import string_types
label_desc: Use image node_id 2 for calling the UnischemaField obj's underlying member method code with example usage: obj.__ne__(other) and returns: unknown