I think you need to clarify with whoever is restricting your Python version which version you can actually use: Python 3.0.1 has been out of support for the better part of 10 years now and hardly anybody ever actually used that particular version (aside from me :))

I have confirmed that Python 3.6 (the oldest version which would receive a fix for this at this point) behaves as expected:

In [1]: '{0:f}'.format(float('nan'))
Out[1]: 'nan'

In [2]: '{0:F}'.format(float('nan'))
Out[2]: 'NAN'

In [3]: '{0:g}'.format(float('nan'))
Out[3]: 'nan'

In [4]: '{0:G}'.format(float('nan'))
Out[4]: 'NAN'

In [5]: '{0:.2f}'.format(float('nan'))
Out[5]: 'nan'