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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 attach(self, handle, filters=None, resolution=None):
 """Attach to an existing SignalFlow computation."""

        params = self._get_params(filters=filters, resolution=resolution)
        c = computation.Computation(
            lambda since: self._transport.attach(handle, params))
        self._computations.add(c)
        return c