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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 register_text_type(content_type, default_encoding, dumper, loader):
 """ Register handling for a text-based content type. :param str content_type: content type to register the hooks for :param str default_encoding: encoding to use if none is present in the request :param dumper: called to decode a string into a dictionary. Calling convention: ``dumper(obj_dict).encode(encoding) -> bytes`` :param loader: called to encode a dictionary to a string. Calling convention: ``loader(obj_bytes.decode(encoding)) -> dict`` The decoding of a text content body takes into account decoding the binary request body into a string before calling the underlying dump/load routines. """

    content_type = headers.parse_content_type(content_type)
    content_type.parameters.clear()
    key = str(content_type)
    _content_types[key] = content_type

    handler = _content_handlers.setdefault(key, _ContentHandler(key))
    handler.dict_to_string = dumper
    handler.string_to_dict = loader
    handler.default_encoding = default_encoding or handler.default_encoding