Add comment as requested by Matthew Brett

Signed-off-by: Mark Hymers <[email protected]>

Author: markhymers

nibabel/nifti1.py

@@ -1274,6 +1274,7 @@ def set_dim_info(self, freq=None, phase=None, slice=None):
         This is stored in one byte in the header
         '''
         for inp in (freq, phase, slice):
+            # Don't use == on None to avoid a FutureWarning in python3
             if inp is not None and inp not in (0, 1, 2):
                 raise HeaderDataError('Inputs must be in [None, 0, 1, 2]')
         info = 0