No module named prompt_toolkit.enums

Question

I am trying to launch Jupyter notebook through my command line and run a python script. At first I was able to launch it via the terminal and run the script, but now the kernel does not launch and it gives me this error - "No module named prompt_toolkit.enums" This is teh whole message from the terminal -

[I 20:33:38.256 NotebookApp] KernelRestarter: restarting kernel (4/5)
WARNING:root:kernel 151cba82-fb9a-4cfc-ba38-3df3f6f5bb61 restarted
Traceback (most recent call last):
  File "/Users/aparihar/anaconda2/lib/python2.7/runpy.py", line 163, in _run_module_as_main
    mod_name, _Error)
  File "/Users/aparihar/anaconda2/lib/python2.7/runpy.py", line 111, in _get_module_details
    __import__(mod_name)  # Do not catch exceptions initializing package
  File "/Users/aparihar/anaconda2/lib/python2.7/site-packages/ipykernel/__init__.py", line 2, in <module>
    from .connect import *
  File "/Users/aparihar/anaconda2/lib/python2.7/site-packages/ipykernel/connect.py", line 13, in <module>
    from IPython.core.profiledir import ProfileDir
  File "/Users/aparihar/anaconda2/lib/python2.7/site-packages/IPython/__init__.py", line 49, in <module>
    from .terminal.embed import embed
  File "/Users/aparihar/anaconda2/lib/python2.7/site-packages/IPython/terminal/embed.py", line 17, in <module>
    from IPython.terminal.interactiveshell import TerminalInteractiveShell
  File "/Users/aparihar/anaconda2/lib/python2.7/site-packages/IPython/terminal/interactiveshell.py", line 16, in <module>
    from prompt_toolkit.enums import DEFAULT_BUFFER, EditingMode
ImportError: No module named prompt_toolkit.enums

I read a lot of questions posted here and on github but i am just not able to resolve this. I even shutdown all the sessions, used pip to install enums and relaunched the Chrome and terminal. Can someone please help?

Thanks!