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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _get_data_from_csv_files(self):
 """Get data from input csv files."""


    all_df = []
    for file_name in self._input_csv_files:
      with _util.open_local_or_gcs(file_name, mode='r') as f:
        all_df.append(pd.read_csv(f, names=self._headers))
    df = pd.concat(all_df, ignore_index=True)
    return df