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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 spline(x,knots,p,i=0.0):
 """Evaluates the ith spline basis given by knots on points in x"""

    assert(p+1<len(knots))
    return np.array([N(float(u),float(i),float(p),knots) for u in x])