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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 read_pcap_from_source(self):
 """ Return a FileStream of the Pcap from the compute node """

        if self._capture_node:
            compute = self._capture_node["node"].compute
            return compute.stream_file(self._project, "tmp/captures/" + self._capture_file_name)