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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 _is_numeric(self, values):
 """Check to be sure values are numbers before doing numerical operations."""

        if len(values) > 0:
            assert isinstance(values[0], (float, int)), \
                "values must be numbers to perform math operations. Got {}".format(
                    type(values[0]))
        return True