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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 _validate(self):
 """ Checks whether all the attributes of this object is valid. """

        if self.region_type not in regions_attributes:
            raise ValueError("'{0}' is not a valid region type in this package"
                             .format(self.region_type))

        if self.coordsys not in valid_coordsys['DS9'] + valid_coordsys['CRTF']:
            raise ValueError("'{0}' is not a valid coordinate reference frame "
                             "in astropy".format(self.coordsys))