Uninstall pip packages GUI

"""
Uninstall pip packages GUI
By Steve Shambles Oct 2019
stevepython.wordpress.com

source: based on an idea from
https://github.com/GDGVIT/pip-gui/blob/master/pip_gui/Package_Management/installedList.py
"""
import subprocess
from subprocess import getoutput
from tkinter import Tk, Button, LabelFrame, messagebox, N, E, W, S
from tkinter.ttk import Combobox

class Pun():
    """Global store"""
    installedPackages = ""
    frame0 = None
    combo1 = None

# Build GUI frame
root = Tk()
root.title('UnPackage')
Pun.frame0 = LabelFrame(root, text="Pip installed packages")
Pun.frame0.grid(padx=8, pady=8, row=0, column=0)

def clkd_uninstall():
    '''uninstall button was clicked'''
    pckg = Pun.combo1.get()
    quest = messagebox.askyesno('Question', 'Are you sure you want to uninstall\n'+str(pckg))
    if quest:
        ex = "pip uninstall"+" "+str(pckg)
        subprocess.Popen(ex)

def get_pips():
    """Get pip installed packages int oa combo list"""
    packages = getoutput('pip freeze')#change to pip3 freeze if required
    Pun.installedPackages = [i.split('==')[0] for i in packages.split('\n')]
    Pun.installedPackages = [i for i in Pun.installedPackages if ' ' not in i]
    #combo box
    Pun.combo1 = Combobox(Pun.frame0)
    Pun.combo1['values'] = (Pun.installedPackages)
    Pun.combo1.current(0)
    Pun.combo1.grid(padx=5, pady=5, row=0, column=0)

#start
get_pips()

#buttons
btn1 = Button(Pun.frame0, bg='skyblue', text='Uninstall selected package', command=clkd_uninstall)
btn1.grid(pady=5, padx=5, row=1, column=0, sticky=N+E+W+S)
btn2 = Button(Pun.frame0, bg='springgreen', text='Refresh package list', command=get_pips)
btn2.grid(pady=5, padx=5, row=2, column=0, sticky=N+E+W+S)

root.mainloop()