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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, fitness_function=None, decode_function=None, fitness_args=None, decode_args=None, fitness_kwargs=None, decode_kwargs=None):
 """Return a copy of this problem. Optionally replace this problems arguments with those passed in. """

        if fitness_function is None:
            fitness_function = self._fitness_function
        if decode_function is None:
            decode_function = self._decode_function
        if fitness_args is None:
            fitness_args = self._fitness_args
        if decode_args is None:
            decode_args = self._decode_args
        if fitness_kwargs is None:
            fitness_kwargs = self._fitness_kwargs
        if decode_kwargs is None:
            decode_kwargs = self._decode_kwargs

        return Problem(
            fitness_function,
            decode_function=decode_function,
            fitness_args=fitness_args,
            decode_args=decode_args,
            fitness_kwargs=fitness_kwargs,
            decode_kwargs=decode_kwargs)