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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 gradient(poly):
 """ Gradient of a polynomial. Args: poly (Poly) : polynomial to take gradient of. Returns: (Poly) : The resulting gradient. Examples: [2, q2, q1] """

    return differential(poly, chaospy.poly.collection.basis(1, 1, poly.dim))