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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 calcperc_sym(b, perc=(0.1,99.9)):
 """ Get symmetrical percentile values Useful for determining clim centered on 0 for difference maps """

    clim = np.max(np.abs(calcperc(b, perc)))
    #clim = (-clim, clim)
    return -clim, clim