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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_variable_from_filepath(self):
 """ Determine the file variable from the filepath. Returns ------- str Best guess of variable name from the filepath """

        try:
            return self.regexp_capture_variable.search(self.filepath).group(1)
        except AttributeError:
            self._raise_cannot_determine_variable_from_filepath_error()