我正在开发一个图形界面，我希望能够在发送后暂停或取消此文件。共有三个按钮（发送、暂停和停止），我已经完成了发送按钮的功能，我现在必须定义两个按钮暂停和取消的功能，请问我该怎么做？这是程序
def moh():
# Open grbl serial port
s = serial.Serial('/dev/ttyS0',115200)
# Open g-code file
f = open(file_path.get(), "r");
# Wake up grbl
s.write("\r\n\r\n".encode('utf8'))
time.sleep(2) # Wait for grbl to initialize
s.flushInput() # Flush startup text in serial input
# Stream g-code to grbl
for line in f:
l = line.strip() # Strip all EOL characters for consistency
print ('Sending: ' + l)
s.write((l + '\n').encode("utf8")) # Send g-code block to grbl
grbl_out = s.readline().decode("utf8") # Wait for grbl response with carriage return
print (' : ' + grbl_out)
# Wait here until grbl is finished to close serial port and file.
raw_input(" Press <Enter> to exit and disable grbl.")
# Close file and serial port
f.close()
s.close()
b1= Button(Outil, text ="Send",background='White', command=moh)
谢谢大家