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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 kill_pid(pid, signal=15):
    '''
    Kill a process by PID.

    .. code-block:: bash

        salt 'minion' ps.kill_pid pid [signal=signal_number]

    pid
        PID of process to kill.

    signal
        Signal to send to the process. See manpage entry for kill
        for possible values. Default: 15 (SIGTERM).

    **Example:**

    Send SIGKILL to process with PID 2000:

    .. code-block:: bash

        salt 'minion' ps.kill_pid 2000 signal=9
    '''
    try:
        psutil.Process(pid).send_signal(signal)
        return True
    except psutil.NoSuchProcess:
        return False