[Python 3] Pinger is a tiny window that tells you your current average ping

pinger.py

import re, subprocess, tkinter, threading

fontsize = 20
timeregex = r'(?<=time=)\d+(?=ms )' # regex to retrieve the # ms
website = 'google.com' # url to ping
pinglimit = 10 # number of pings to average
pinginterval = 500 # ms delay between pings
pings = [] # array to hold pings

def avg(l):
    length = len(l)
    if length == 0:
        return length
    return int(sum(l) / float(len(l)))

def getPing():
    cmd = ['ping', website, '-n', '1']
    startupinfo = subprocess.STARTUPINFO()
    startupinfo.dwFlags |= subprocess.STARTF_USESHOWWINDOW
    proc = subprocess.Popen(cmd, stdout=subprocess.PIPE, startupinfo=startupinfo)
    for line in proc.stdout:
        ping = re.findall(timeregex, str(line))
        if len(ping) > 0:
            if len(pings) > pinglimit:
                del pings[0]
            pings.append(int(ping[0]))
    proc.wait()
    return "-"

class mainForm():
    def __init__(self):
        self.root = tkinter.Tk()
        self.label = tkinter.Label(text='', font=('Helvetica', fontsize))
        self.label.pack()
        self.update_clock()
        self.root.mainloop()
        
    def update_clock(self):
        threading.Thread(target=getPing).start()
        self.label.configure(text=str(avg(pings)))
        self.root.after(pinginterval, self.update_clock)
        
if __name__ == '__main__':
    app = mainForm()