old_contents: """test_preprocess.py"""
  import numpy as np
  from impyute.util import preprocess
  from impyute.imputation.cs import mean
  
  # pylint:disable=redefined-builtin
  try:
      raise ModuleNotFoundError
  except NameError:
      class ModuleNotFoundError(Exception):
          "placeholder required for python2.7"
          pass
  except ModuleNotFoundError:
      pass
  
  # pylint:disable=unused-argument
  @preprocess
  def mul(arr, **kwargs):
      """Some function that performs an inplace operation on the input. Accepts kwargs"""
      arr *= 25
      return arr
  
  
  @preprocess
  def mul_no_kwargs(arr):
      """Some function that performs an inplace operation on the input"""
      arr *= 25
      return arr
  
  
  def test_inplace_false():
      """Input should be unchanged if inplace set to false"""
      A = np.ones((5, 5))
      A_copy = A.copy()
      mul(A, inplace=False)
      assert A[0, 0] == A_copy[0, 0]
  
  
  def test_inplace_true():
      """Input may be changed if inplace set to true and operation is inplace"""
      A = np.ones((5, 5))
      A_copy = A.copy()
      mul(A, inplace=True)
      assert A[0, 0] != A_copy[0, 0]
  
  
  def test_inplace_false_nokwargs():
      """Test that passed in function doesn't need to set kwargs as parameters
      Input should be unchanged if inplace set to false
      """
      A = np.ones((5, 5))
      A_copy = A.copy()
      # pylint: disable = unexpected-keyword-arg
      mul_no_kwargs(A, inplace=False)
      # pylint: enable = unexpected-keyword-arg
      assert A[0, 0] == A_copy[0, 0]
  
  
  def test_inplace_true_nokwargs():
      """Test that passed in function doesn't need to set kwargs as parameters
      Input may be changed if inplace set to true and operation is inplace
      """
      A = np.ones((5, 5))
      A_copy = A.copy()
      # pylint: disable = unexpected-keyword-arg
      mul_no_kwargs(A, inplace=True)
      # pylint: enable = unexpected-keyword-arg
      assert A[0, 0] != A_copy[0, 0]
  
  
  def test_pandas_input():
      """ Input: DataFrame, Output: DataFrame """
      # Skip this test if you don't have pandas
      try:
          import pandas as pd
      except (ModuleNotFoundError, ImportError):
          assert True
          return
  
      # Create a DataFrame with a NaN
      A = np.arange(25).reshape((5, 5)).astype(np.float)
      A[0, 0] = np.nan
      A = pd.DataFrame(A)
  
      # Assert that the output is a DataFrame
      assert isinstance(mean(A), pd.DataFrame)
  
new_contents: """test_preprocess.py"""
  import pytest
  import numpy as np
  from impyute.util import preprocess
  from impyute.imputation.cs import mean
  
  # pylint:disable=redefined-builtin
  try:
      raise ModuleNotFoundError
  except NameError:
      class ModuleNotFoundError(Exception):
          "placeholder required for python2.7"
          pass
  except ModuleNotFoundError:
      pass
  
  # pylint:disable=unused-argument
  @preprocess
  def mul(arr, **kwargs):
      """Some function that performs an inplace operation on the input. Accepts kwargs"""
      arr *= 25
      return arr
  
  
  @preprocess
  def mul_no_kwargs(arr):
      """Some function that performs an inplace operation on the input"""
      arr *= 25
      return arr
  
  
  def test_inplace_false():
      """Input should be unchanged if inplace set to false"""
      A = np.ones((5, 5))
      A_copy = A.copy()
      mul(A, inplace=False)
      assert A[0, 0] == A_copy[0, 0]
  
  
  def test_inplace_true():
      """Input may be changed if inplace set to true and operation is inplace"""
      A = np.ones((5, 5))
      A_copy = A.copy()
      mul(A, inplace=True)
      assert A[0, 0] != A_copy[0, 0]
  
  
  def test_inplace_false_nokwargs():
      """Test that passed in function doesn't need to set kwargs as parameters
      Input should be unchanged if inplace set to false
      """
      A = np.ones((5, 5))
      A_copy = A.copy()
      # pylint: disable = unexpected-keyword-arg
      mul_no_kwargs(A, inplace=False)
      # pylint: enable = unexpected-keyword-arg
      assert A[0, 0] == A_copy[0, 0]
  
  
  def test_inplace_true_nokwargs():
      """Test that passed in function doesn't need to set kwargs as parameters
      Input may be changed if inplace set to true and operation is inplace
      """
      A = np.ones((5, 5))
      A_copy = A.copy()
      # pylint: disable = unexpected-keyword-arg
      mul_no_kwargs(A, inplace=True)
      # pylint: enable = unexpected-keyword-arg
      assert A[0, 0] != A_copy[0, 0]
  
  
  def test_pandas_input():
      """ Input: DataFrame, Output: DataFrame """
      # Skip this test if you don't have pandas
      pytest.importorskip('pandas')
  
      # Create a DataFrame with a NaN
      A = np.arange(25).reshape((5, 5)).astype(np.float)
      A[0, 0] = np.nan
      A = pd.DataFrame(A)
  
      # Assert that the output is a DataFrame
      assert isinstance(mean(A), pd.DataFrame)
  
subject: use pytest way to skip