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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 add( self, symbol, base_value, dimensions, tex_repr=None, offset=None, prefixable=False, ):
 """ Add a symbol to this registry. Parameters symbol : str The name of the unit base_value : float The scaling from the units value to the equivalent SI unit with the same dimensions dimensions : expr The dimensions of the unit tex_repr : str, optional The LaTeX representation of the unit. If not provided a LaTeX representation is automatically generated from the name of the unit. offset : float, optional If set, the zero-point offset to apply to the unit to convert to SI. This is mostly used for units like Farhenheit and Celcius that are not defined on an absolute scale. prefixable : bool If True, then SI-prefix versions of the unit will be created along with the unit itself. """

        from unyt.unit_object import _validate_dimensions

        self._unit_system_id = None

        # Validate
        if not isinstance(base_value, float):
            raise UnitParseError(
                "base_value (%s) must be a float, got a %s."
                % (base_value, type(base_value))
            )

        if offset is not None:
            if not isinstance(offset, float):
                raise UnitParseError(
                    "offset value (%s) must be a float, got a %s."
                    % (offset, type(offset))
                )
        else:
            offset = 0.0

        _validate_dimensions(dimensions)

        if tex_repr is None:
            # make educated guess that will look nice in most cases
            tex_repr = r"\rm{" + symbol.replace("_", r"\ ") + "}"

        # Add to lut
        self.lut[symbol] = (base_value, dimensions, offset, tex_repr, prefixable)