def quality_scrub(df, target_cols = ['quality_1', 'quality_2', 'quality_3']):
  """
  Definition:
  Filters a dataframe where each target_col does not contain 'no_cough'

  Args:
  df: Required. A dataframe containing the target columns
  target_cols: default = ['quality_1', 'quality_2', 'quality_3']. 

  Returns:
  Returns a filtered dataframe where each target_col does not contain 'no_cough'
  """
  for col in target_cols:
    df = df[df[col] != 'no_cough']
  return df