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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 copy(self, path, dest, raise_if_exists=False):
 """ Copies the contents of a single file path to dest """

        if raise_if_exists and dest in self.get_all_data():
            raise RuntimeError('Destination exists: %s' % path)
        contents = self.get_all_data()[path]
        self.get_all_data()[dest] = contents