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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_pid_status(pid="self"):
 """ Returns the system process sstatus. :param pid: The process ID. :returns: The system process status. :rtype: dict """

    data = {}
    with open("/proc/%s/status" % (pid,), "rb") as status_file:
        for row in status_file:
            fields = row.split()
            if fields and fields[0] in [b"VmRSS:", b"Threads:", b"FDSize:"]:
                try:
                    data[fields[0].decode("ascii")[:-1]] = int(fields[1])
                except ValueError:
                    data[fields[0].decode("ascii")[:-1]] = fields[1].decode("ascii")
    return data