Description of problem:
$ cat test.py
#!/usr/bin/python

floatf = 12.3
infinf = float("inf")
strinf = "inf"

fmt = "{0:>4.4}"

print(fmt.format(floatf))
print(fmt.format(infinf))
print(fmt.format(strinf))

This prints on RHEL 7 / Fedora 23 / Fedora 24 using their Python 2 / Python 3:

12.3
 inf
 inf

But on RHEL 6 the output is:

12.3
.0inf
 inf


Version-Release number of selected component (if applicable):
python-2.6.6-64.el6.x86_64