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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 lineprotocol( cls=None, *, schema: Optional[Mapping[str, type]] = None, rm_none: bool = False, extra_tags: Optional[Mapping[str, str]] = None, placeholder: bool = False ):
 """Adds ``to_lineprotocol`` method to arbitrary user-defined classes :param cls: Class to monkey-patch :param schema: Schema dictionary (attr/type pairs). :param rm_none: Whether apply a regex to remove ``None`` values. If ``False``, passing ``None`` values to boolean, integer or float or time fields will result in write errors. Setting to ``True`` is "safer" but impacts performance. :param extra_tags: Hard coded tags to be added to every point generated. :param placeholder: If no field attributes are present, add a placeholder attribute (``_``) which is always equal to ``True``. This is a workaround for creating field-less points (which is not supported natively by InfluxDB) """


    def _lineprotocol(cls):
        _schema = schema or getattr(cls, '__annotations__', {})
        f = _make_serializer(cls.__name__, _schema, rm_none, extra_tags, placeholder)
        cls.to_lineprotocol = f
        return cls

    return _lineprotocol(cls) if cls else _lineprotocol