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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_content_type(header):
 """Parse the "Content-Type" header."""

    typ = subtyp = None; options = {}
    typ, pos = expect_re(re_token, header, 0)
    _, pos = expect_lit('/', header, pos)
    subtyp, pos = expect_re(re_token, header, pos)
    ctype = header[:pos] if subtyp else ''
    while pos < len(header):
        _, pos = accept_ws(header, pos)
        _, pos = expect_lit(';', header, pos)
        _, pos = accept_ws(header, pos)
        name, pos = expect_re(re_token, header, pos)
        _, pos = expect_lit('=', header, pos)
        char = lookahead(header, pos)
        if char == '"':
            value, pos = expect_re(re_qstring, header, pos)
            value = re_qpair.sub('\\1', value)
        elif char:
            value, pos = expect_re(re_token, header, pos)
        if name and value is not None:
            options[name] = value
    return ctype, options