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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, klass=_x):
 """A new chain beginning with the current chain tokens and argument. """

        chain = super().copy()
        new_chain = klass(chain._args[0])
        new_chain._tokens = [[
            chain.compose, [], {},
        ]]
        return new_chain