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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 sobel(image, mask=None):
    '''Calculate the absolute magnitude Sobel to find the edges

    image - image to process
    mask - mask of relevant points

    Take the square root of the sum of the squares of the horizontal and
    vertical Sobels to get a magnitude that's somewhat insensitive to
    direction.

    Note that scipy's Sobel returns a directional Sobel which isn't
    useful for edge detection in its raw form.
    '''
    return np.sqrt(hsobel(image,mask)**2 + vsobel(image,mask)**2)