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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 move_to(self, folder):
 """Moves the email to the folder specified by the folder parameter. Args: folder: A string containing the folder ID the message should be moved to, or a Folder instance """

        if isinstance(folder, Folder):
            self.move_to(folder.id)
        else:
            self._move_to(folder)