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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 _get_int64(data, position, dummy0, dummy1, dummy2):
 """Decode a BSON int64 to bson.int64.Int64."""

    end = position + 8
    return Int64(_UNPACK_LONG(data[position:end])[0]), end