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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 _remove_data_dir_path(self, inp=None):
 # import string """Remove the data directory path from filenames"""

        # need to add a check in here to make sure data_dir path is actually in
        # the filename
        if inp is not None:
            split_str = os.path.join(self.data_path, '')
            return inp.apply(lambda x: x.split(split_str)[-1])