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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_multiindex(self, obj):
 """validate that we can store the multi-index; reset and return the new object """

        levels = [l if l is not None else "level_{0}".format(i)
                  for i, l in enumerate(obj.index.names)]
        try:
            return obj.reset_index(), levels
        except ValueError:
            raise ValueError("duplicate names/columns in the multi-index when "
                             "storing as a table")