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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 html5_parse_simple_color(input):
 """ Apply the simple color parsing algorithm from section 2.4.6 of HTML5. """

    # 1. Let input be the string being parsed.
    #
    # 2. If input is not exactly seven characters long, then return an
    #    error.
    if not isinstance(input, unicode) or len(input) != 7:
        raise ValueError(
            u"An HTML5 simple color must be a Unicode string "
            u"exactly seven characters long."
        )

    # 3. If the first character in input is not a U+0023 NUMBER SIGN
    #    character (#), then return an error.
    if not input.startswith('#'):
        raise ValueError(
            u"An HTML5 simple color must begin with the "
            u"character '#' (U+0023)."
        )

    # 4. If the last six characters of input are not all ASCII hex
    #    digits, then return an error.
    if not all(c in string.hexdigits for c in input[1:]):
        raise ValueError(
            u"An HTML5 simple color must contain exactly six ASCII hex digits."
        )

    # 5. Let result be a simple color.
    #
    # 6. Interpret the second and third characters as a hexadecimal
    #    number and let the result be the red component of result.
    #
    # 7. Interpret the fourth and fifth characters as a hexadecimal
    #    number and let the result be the green component of result.
    #
    # 8. Interpret the sixth and seventh characters as a hexadecimal
    #    number and let the result be the blue component of result.
    #
    # 9. Return result.
    return HTML5SimpleColor(
        int(input[1:3], 16),
        int(input[3:5], 16),
        int(input[5:7], 16)
    )