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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 cross_product_compare(start, candidate1, candidate2):
 """Compare two relative changes by their cross-product. This is meant to be a way to determine which vector is more "inside" relative to ``start``. .. note:: This is a helper for :func:`_simple_convex_hull`. Args: start (numpy.ndarray):
 The start vector (as 1D NumPy array with 2 elements). candidate1 (numpy.ndarray):
 The first candidate vector (as 1D NumPy array with 2 elements). candidate2 (numpy.ndarray):
 The second candidate vector (as 1D NumPy array with 2 elements). Returns: float: The cross product of the two differences. """

    delta1 = candidate1 - start
    delta2 = candidate2 - start
    return cross_product(delta1, delta2)