code: def rfft_input_validation(x):
      if not x.dtype.is_floating:
          raise TypeError(
              f"Invalid FFT input: `x` must be of a real dtype. Received: {x.dtype}"
          )
      return x
  
imports: import math
  from typing import Union, Optional, Tuple, List, Literal, Sequence, Callable
  import tensorflow
  from ivy.func_wrapper import inputs_to_ivy_arrays, output_to_native_arrays, with_unsupported_dtypes, with_supported_dtypes, with_supported_device_and_dtypes
  from ..None import backend_version
  import ivy
  from ivy.functional.ivy.layers import _handle_padding, _get_num_padded_values, _validate_max_pool_params, _depth_max_pooling_helper
  from ivy.functional.ivy.experimental.layers import _padding_ceil_mode, _get_size
label_desc: Use image node_id 42 for calling a global function with example usage: rfft_input_validation(x) and returns: x