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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 _verify(self):
 """Verify that the edges define a curved polygon. This may not be entirely comprehensive, e.g. won't check self-intersection of the defined polygon. .. note:: This currently checks that edge endpoints match **exactly** but allowing some roundoff may be desired. Raises: ValueError: If there are fewer than two sides. ValueError: If one of the sides is not in 2D. ValueError: If consecutive sides don't share an endpoint. """

        if self._num_sides < 2:
            raise ValueError("At least two sides required.")

        for prev, curr in six.moves.zip(self._edges, self._edges[1:]):
            self._verify_pair(prev, curr)
        # Now we check that the final edge wraps around.
        prev = self._edges[-1]
        curr = self._edges[0]
        self._verify_pair(prev, curr)