Python if __name__ = "__main__": If Else Functionality

I'm writing a script that will call a different function depending on how many input variables are passed into the python script. So far, I have my python script structured like below:

funcA():
...
funcB():
...

if __name__ == "__main__":
    if len(sys.argv) is 5:
        funcA(sys.argv[1],sys.argv[2],sys.argv[3],sys.argv[4],sys.argv[5])
    elif len(sys.argv) is 7:
        funcB(sys.argv[1],sys.argv[2],sys.argv[3],sys.argv[4],sys.argv[5],sys.argv[6],sys.argv[7])

But when I execute the script, none of my parameters are being passed. Is there something I'm doing wrong in my if name statement?