Get CPU usage in %

cpu.py

import time

def cpuUsage():
    with open('/proc/stat', 'r') as statFile:
        cpuValues = [int(v) for v in statFile.readline().strip().split()[1:]]
        total1 = sum(cpuValues)
        work_1 = sum(cpuValues[0:3])

    time.sleep(2)   # Sample 2 seconds

    with open('/proc/stat', 'r') as statFile:
        cpuValues = [int(v) for v in statFile.readline().strip().split()[1:]]
        total2 = sum(cpuValues)
        work_2 = sum(cpuValues[0:3])

    return (float(work_2 - work_1) / (total2 - total1))

if __name__ == '__main__':
    print 'CPU usage in last 2 seconds:', cpuUsage() * 100, '\b%'