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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 _validate_index_level(self, level):
 """ Validate index level. For single-level Index getting level number is a no-op, but some verification must be done like in MultiIndex. """

        if isinstance(level, int):
            if level < 0 and level != -1:
                raise IndexError("Too many levels: Index has only 1 level,"
                                 " %d is not a valid level number" % (level, ))
            elif level > 0:
                raise IndexError("Too many levels:"
                                 " Index has only 1 level, not %d" %
                                 (level + 1))
        elif level != self.name:
            raise KeyError('Level %s must be same as name (%s)' %
                           (level, self.name))