When using PyMol with Python 3.6 the following errors occur.
AttributeError Exception in Tk callback
Function: <bound method="" Normal.inc_fontsize_dialog="" of="" <pmg_tk.skins.normal.Normal="" object="" at="" 0x7faabc10fcc0="">> (type: <class 'method'="">)
Args: ()
Traceback (innermost last):
File "/usr/local/lib/python3.6/dist-packages/Pmw/Pmw_2_0_1/lib/PmwBase.py", line 1776, in call
return self.func(*args)
File "/usr/local/lib/python3.6/dist-packages/pmg_tk/skins/normal/init.py", line 147, in inc_fontsize_dialog
col = iter(range(5)).next
AttributeError: 'range_iterator' object has no attribute 'next'
Setting: internal_gui_control_size set to 20.
AttributeError Exception in Tk callback
Function: <bound method="" Normal.inc_fontsize_dialog="" of="" <pmg_tk.skins.normal.Normal="" object="" at="" 0x7faabc10fcc0="">> (type: <class 'method'="">)
Args: ()
Traceback (innermost last):
File "/usr/local/lib/python3.6/dist-packages/Pmw/Pmw_2_0_1/lib/PmwBase.py", line 1776, in call
return self.func(*args)
File "/usr/local/lib/python3.6/dist-packages/pmg_tk/skins/normal/init.py", line 147, in inc_fontsize_dialog
col = iter(range(5)).next
AttributeError: 'range_iterator' object has no attribute 'next'
Probably, this error can be corrected by replacing lines 147, 152 in pmg_tk/skins/normal/init.py ("col = iter(range(5)).next") by "col = lambda: next(iter(range(5)))".
this is fixed in fixed in pymol rev 4182
https://sourceforge.net/p/pymol/code/4182/