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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 project_meta(self, attributes):
 """ Projects the specified metadata attributes to new region fields :param attributes: a list of metadata attributes :return: a new GDataframe with additional region fields """

        if not isinstance(attributes, list):
            raise TypeError('attributes must be a list')
        meta_to_project = self.meta[attributes].applymap(lambda l: ", ".join(l))
        new_regs = self.regs.merge(meta_to_project, left_index=True, right_index=True)
        return GDataframe(regs=new_regs, meta=self.meta)