raspberry pi - How to import variable (sensor input) & update it from one python script to another? -

i'm setting sensors raspberry pi in python. total python newbie here.

each sensor has it's own script read sensor , there script drives lcd display , displays imported variable sensor script.

i've gotten far working scripts run sensors , generate output, however, cannot seem import variables (temperature & ph) lcd display script. also, once have imported variables, how instruct lcd script "refresh" , fetch updated variable?

here's trimmed down version of have far, i've omitted sensor , data logging parts of each script. simplicity, script_display lcd driver, , ph_script ph , temp_script temperature.

here's simplified version of scripts:

script_display.py

import sys sys.path.insert(0, '/home/pi/raspberry-pi-sample-code') import ph_script import temp_script ph_script import ph_main temp_script import get_temp import time  while true:         print ph.ph_main(ph_output)         print get_temp(temp)         time.sleep(1) 

temp_script.py

from w1thermsensor import w1thermsensor import time  #get temperature def get_temp():         global temp         sensor = w1thermsensor(w1thermsensor.therm_sensor_ds18b20, "031683a0a4ff")         activate_temp = sensor.get_temperature()         temp = str(activate_temp)         return temp  #read temp frequency def read():         threading.timer(0.5, read).start()         get_temp()         time.sleep(1)     try:             while true:                     read()                     get_temp()                     print get_temp()   except keyboardinterrupt:                        print("program ended user") 

ph_script.py

def ph_main(): 

lots , lots of code activate ph probe, , other variables, variable ph_output returns string, ph_output

    try:         while true:                    global ph_output                   dev.send_cmd("r")                   lines = dev.read_lines()                   in range(len(lines)):                                 print lines[i]                                 if lines[i][0] != '*':                                          print lines[i]                                          ph_output = str(lines[i])                                          return ph_output                                          time.sleep(delaytime) try:         while true:                 ph_main()      except keyboardinterrupt:                                print("continuous polling stopped") 

so, again, first question, how pass global variables display script? , two, how instruct display script 'refresh' variables?

the error getting is:

    traceback (most recent call last):   file "script_display.py", line 8, in <module>     print ph.ph_main(ph_output) nameerror: name 'ph_output' not defined 

looking forward input , time + help!