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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_pair(prev, curr):
 """Verify a pair of sides share an endpoint. .. note:: This currently checks that edge endpoints match **exactly** but allowing some roundoff may be desired. Args: prev (.Curve):
 "Previous" curve at piecewise junction. curr (.Curve):
 "Next" curve at piecewise junction. Raises: ValueError: If the previous side is not in 2D. ValueError: If consecutive sides don't share an endpoint. """

        if prev._dimension != 2:
            raise ValueError("Curve not in R^2", prev)

        end = prev._nodes[:, -1]
        start = curr._nodes[:, 0]
        if not _helpers.vector_close(end, start):
            raise ValueError(
                "Not sufficiently close",
                "Consecutive sides do not have common endpoint",
                prev,
                curr,
            )