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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 colors(self, value):
 """ Converts color strings into a color listing. """

        if isinstance(value, str):
            # Must import here to avoid recursive import
            from .palettes import PALETTES

            if value not in PALETTES:
                raise YellowbrickValueError(
                    "'{}' is not a registered color palette".format(value)
                )
            self._colors = copy(PALETTES[value])
        elif isinstance(value, list):
            self._colors = value
        else:
            self._colors = list(value)