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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_pid(rundir, process_type=PROCESS_TYPE, name=None):
 """ Get the pid from the pid file in the run directory, using the given process type and process name for the filename. @returns: pid of the process, or None if not running or file not found. """

    pidPath = get_pidpath(rundir, process_type, name)
    log.log('run', 'pidfile for %s %s is %s' % (process_type, name, pidPath))

    if not os.path.exists(pidPath):
        return

    pidFile = open(pidPath, 'r')
    pid = pidFile.readline()
    pidFile.close()
    if not pid or int(pid) == 0:
        return

    return int(pid)