code: def as_dtype(type_value):
      """Converts the given `type_value` to a `DType`.
  
      Args:
        type_value: A value that can be converted to a `tf.DType` object. This may
          currently be a `tf.DType` object, a [`DataType`
          enum](https://www.tensorflow.org/code/tensorflow/core/framework/types.proto),
          a string type name, or a `numpy.dtype`.
  
      Returns:
        A `DType` corresponding to `type_value`.
  
      Raises:
        TypeError: If `type_value` cannot be converted to a `DType`.
      """
      if isinstance(type_value, DType):
          return type_value
  
      try:
          return _INTERN_TABLE[type_value]
      except KeyError:
          pass
  
      try:
          return _STRING_TO_TF[type_value]
      except KeyError:
          pass
  
      try:
          return _PYTHON_TO_TF[type_value]
      except KeyError:
          pass
  
      if isinstance(type_value, np.dtype):
          # The numpy dtype for strings is variable length. We can not compare
          # dtype with a single constant (np.string does not exist) to decide
          # dtype is a "string" type. We need to compare the dtype.type to be
          # sure it's a string type.
          if (
              type_value.type == np.string_
              or type_value.type == np.unicode_
          ):
              return string
  
      if isinstance(type_value, (type, np.dtype)):
          for key, val in _NP_TO_TF:
              try:
                  if key == type_value:
                      return val
              except TypeError as e:
                  raise TypeError(
                      "Cannot convert {} to a dtype. {}".format(
                          type_value, e
                      )
                  )
  
      raise TypeError(
          "Cannot convert value %r to a TensorFlow DType." % type_value
      )
  
imports: import numpy
  from .None import pywrap_tensorflow
  from tensorboard.compat.proto import types_pb2
label_desc: Use image node_id 1 for calling a global function with example usage: as_dtype(type_value) and returns: type_value, _INTERN_TABLE, _STRING_TO_TF, _PYTHON_TO_TF, string, val