Organize Python dependencies

Author: mdmintz

setup.py

@@ -161,9 +161,9 @@
         'pygments==2.7.4;python_version>="3.5"',
         'traitlets==4.3.3;python_version<"3.7"',
         'traitlets==5.0.5;python_version>="3.7"',
-        'ipython==5.10.0;python_version<"3.5"',
         'prompt-toolkit==1.0.18;python_version<"3.6"',
         'prompt-toolkit==3.0.15;python_version>="3.6"',
+        'ipython==5.10.0;python_version<"3.5"',
         'ipython==6.5.0;python_version>="3.5" and python_version<"3.6"',
         'ipython==7.16.1;python_version>="3.6" and python_version<"3.7"',
         'ipython==7.20.0;python_version>="3.7"',