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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 _get_global_color_table(colors):
 """Return a color table sorted in descending order of count. """

    global_color_table = b''.join(c[0] for c in colors.most_common())
    full_table_size = 2**(1+int(get_color_table_size(len(colors)), 2))
    repeats = 3 * (full_table_size - len(colors))
    zeros = struct.pack('<{}x'.format(repeats))
    return global_color_table + zeros