grt=["thousand","million","billion","trillion","quadrillion","quintillion","sextillion","septillion","octillion","nonillion","decillion","undecillion","duodecillion","tredecillion","quattuor-decillion","quindecillion","sexdecillion","septen-decillion","octodecillion","novemdecillion","vigintillion"]
e=["sixty","million","billion","trillion","quadrillion","quintillion","sextillion","septillion","octillion"]
def sep():
global e
global grt
for i in range(1,len(e)):
if (e[i] in grt and e[i-1] in grt)==True:
e.remove(e[i])
while all(((i in grt) and (e[e.index(i)-1] in grt)) for i in e[1:len(e)])!=False:
sep()
print(e)
i am expecting that the last statement print(e) would print ["sixty"] but its not printing that.