class_docstr: Represents the type of a TensorFlow function.
  
  FunctionType is the canonical way to represent the input/output contract of
  all kinds of functions within the tf.function domain, including:
    - Polymorphic Function
    - Concrete Function
    - Atomic Function
  
  It provides consistent, centralized and layered logic for:
    - Canonicalization of Python input arguments
    - Type-based dispatch to monomorphic functions
    - Packing/unpacking structured python values to Tensors
    - Generation of structured placeholder values for tracing
  
  Additionaly, it also provides:
    - Lossless serialization
    - Native integration with Python function signature representation
    - Seamless migration from older representation formats
code: def __hash__(self) -> int:
      return hash(
          (tuple(self.parameters.items()), tuple(self.captures.items()))
      )
  
imports: import collections
  import inspect
  from typing import Any, Callable, Dict, List, Mapping, Optional, Sequence, Tuple
  from absl import logging
  from tensorflow.core.function import trace_type
  from tensorflow.core.function.polymorphism import function_type_pb2
  from tensorflow.core.function.trace_type import serialization
  from tensorflow.python.types import core
  from tensorflow.python.types import trace
label_desc: Use image node_id 20 for calling the FunctionType obj's underlying member method code with example usage: obj.__hash__() and returns: hash