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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 circular_mask(size):
 """Create a circular mask for an array Useful when sampling rasters for a laser shot """

    r = size/2
    c = (r,r)
    y,x = np.ogrid[-c[0]:size-c[0], -c[1]:size-c[1]]
    mask = ~(x*x + y*y <= r*r)
    return mask