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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 hex2rgb(h):
 """ Convert hex colors to RGB tuples Parameters h : str String hex color value '255,0,51' """

    if not h.startswith('#') or len(h) != 7:
        raise ValueError("Does not look like a hex color: '{0}'".format(h))
    return ','.join(map(str, (
        int(h[1:3], 16),
        int(h[3:5], 16),
        int(h[5:7], 16),
    )))