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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 parse_hex_color(value):
 """ Convert a CSS color in hexadecimal notation into its R, G, B components. :param value: A CSS color in hexadecimal notation (a string like '#000000'). :return: A tuple with three integers (with values between 0 and 255) corresponding to the R, G and B components of the color. :raises: :exc:`~exceptions.ValueError` on values that can't be parsed. """

    if value.startswith('#'):
        value = value[1:]
    if len(value) == 3:
        return (
            int(value[0] * 2, 16),
            int(value[1] * 2, 16),
            int(value[2] * 2, 16),
        )
    elif len(value) == 6:
        return (
            int(value[0:2], 16),
            int(value[2:4], 16),
            int(value[4:6], 16),
        )
    else:
        raise ValueError()