install_windows.py

import os
import pip
import ctypes, sys

def is_admin():
    try:
        return ctypes.windll.shell32.IsUserAnAdmin()
    except:
        return False

os.chdir(os.path.dirname(os.path.realpath(__file__)))

def install(package):
    pip.main(['install', package])

if __name__ == '__main__':
    if is_admin():
        fh = open('requirements.txt')
        for line in fh:
            install(line)
        fh.close()
    else:
        ctypes.windll.shell32.ShellExecuteW(
            None, "runas", sys.executable, 
            os.path.realpath(__file__), None, 1)