def __init__(self, default_value=NoDefaultSpecified, **metadata):
        """Create a TraitType.
        """
        if default_value is not NoDefaultSpecified:
            self.default_value = default_value

        if len(metadata) > 0:
            if len(self.metadata) > 0:
                self._metadata = self.metadata.copy()
                self._metadata.update(metadata)
            else:
                self._metadata = metadata
        else:
            self._metadata = self.metadata

        self.init()
dataset/ETHPy150Open enthought/depsolver/depsolver/bundled/traitlets/_implementation.py/TraitType.__init__/original