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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 strel_disk(radius):
 """Create a disk structuring element for morphological operations radius - radius of the disk """

    iradius = int(radius)
    x,y     = np.mgrid[-iradius:iradius+1,-iradius:iradius+1]
    radius2 = radius * radius
    strel   = np.zeros(x.shape)
    strel[x*x+y*y <= radius2] = 1
    return strel