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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 _norm_cmap(values, cmap, normalize, cm, vmin=None, vmax=None):
 """ Normalize and set colormap. Taken from geopandas@0.2.1 codebase, removed in geopandas@0.3.0. """


    mn = min(values) if vmin is None else vmin
    mx = max(values) if vmax is None else vmax
    norm = normalize(vmin=mn, vmax=mx)
    n_cmap = cm.ScalarMappable(norm=norm, cmap=cmap)
    return n_cmap