docstr: Test any conversion from a float dtype to an other.
code: def test_float_conversion_dtype(self):
      """Test any conversion from a float dtype to an other."""
  
      x = np.array([-1, 1])
      # Test all combinations of dtypes conversions
      dtype_combin = np.array(
          np.meshgrid(
              TestOutputPreprocessing.float_dtype_list,
              TestOutputPreprocessing.float_dtype_list,
          )
      ).T.reshape(-1, 2)
  
      for dtype_in, dtype_out in dtype_combin:
          x = x.astype(dtype_in)
          y = processing_utils._convert(x, dtype_out)
          assert y.dtype == np.dtype(dtype_out)
  
imports: import os
  import shutil
  import tempfile
  from copy import deepcopy
  from pathlib import Path
  from unittest.mock import patch
  import ffmpy
  import numpy
  import pytest
  from gradio_client import media_data
  from PIL import Image, ImageCms
  from gradio import processing_utils, utils
label_desc: Use image node_id 1 for calling the TestOutputPreprocessing obj's underlying member method code with example usage: obj.test_float_conversion_dtype() without return types