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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(content_type):
 """ Return a tuple of content type and charset. :param content_type: A string describing a content type. """

    if '; charset=' in content_type:
        return tuple(content_type.split('; charset='))
    else:
        if 'text' in content_type:
            encoding = 'ISO-8859-1'
        else:
            try:
                format = formats.find_by_content_type(content_type)
            except formats.UnknownFormat:
                encoding = 'ISO-8859-1'
            else:
                encoding = format.default_encoding or 'ISO-8859-1'

        return (content_type, encoding)