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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 precompute_sharp_round(nxk, nyk, xc, yc):
 """ Pre-computes mask arrays to be used by the 'sharp_round' function for roundness computations based on two- and four-fold symmetries. """


    # Create arrays for the two- and four-fold symmetry computations:
    s4m = np.ones((nyk,nxk),dtype=np.int16)
    s4m[yc, xc] = 0

    s2m = np.ones((nyk,nxk),dtype=np.int16)
    s2m[yc, xc] = 0
    s2m[yc:nyk, 0:xc]     = -1;
    s2m[0:yc+1, xc+1:nxk] = -1;

    return s2m, s4m