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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 rotate(f,x,theta=0):
    '''
    Returns a function that takes as input the 1D vector along the angle
    given a function that takes in 2D input
    '''
    f_R = lambda b: f(np.array([[x*np.cos(theta)-b*np.sin(theta)],
                                [x*np.sin(theta)+b*np.cos(theta)]]))
    return f_R