It has been a few years since this was answered, but as of Python 3.6 (PEP498) you could use the new f-strings
:
numbers = [23.23, 0.123334987, 1, 4.223, 9887.2]
for number in numbers:
print(f'{number:9.4f}')
Prints:
23.2300
0.1233
1.0000
4.2230
9887.2000