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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 detect_version_str(self):
 """ Try to detect version of package from command help text. Bit of a long shot as they are typically included """

        help_text = run_matlab_cmd("help('{}')".format(self.test_func))
        if not help_text:
            raise ArcanaRequirementNotFoundError(
                "Did not find test function '{}' for {}"
                .format(self.test_func, self))
        return self.parse_help_text(help_text)