def fact(n):
"""
Return 1, if n is 1 or below,
otherwise, return n * fact(n-1).
return 1 if n <= 1 else n * fact(n - 1)
Show factorial for i,
where i ranges from 1 to 20.
for i in range(1, 21):
print(i, ": ", fact(i), sep="")
