Jupyter Notebook not connecting to python kernel

I have previously installed python 3.7 from python.org and later installed anaconda python distribution. When I launch the Jupyter notebook the kernel is failing to get connected. What could be the problem I tried reinstalling but it didn't work.

Below is the error I got.

 [I 00:23:53.252 NotebookApp] KernelRestarter: restarting kernel (4/5), new random ports
Traceback (most recent call last):
  File "C:\Users\lenovo\AppData\Local\Programs\Python\Python37\lib\runpy.py", line 193, in _run_module_as_main
    "__main__", mod_spec)
  File "C:\Users\lenovo\AppData\Local\Programs\Python\Python37\lib\runpy.py", line 85, in _run_code
    exec(code, run_globals)
  File "C:\Users\lenovo\AppData\Local\Programs\Python\Python37\lib\site-packages\ipykernel_launcher.py", line 15, in <module>
    from ipykernel import kernelapp as app
  File "C:\Users\lenovo\AppData\Local\Programs\Python\Python37\lib\site-packages\ipykernel\__init__.py", line 2, in <module>
    from .connect import *
  File "C:\Users\lenovo\AppData\Local\Programs\Python\Python37\lib\site-packages\ipykernel\connect.py", line 13, in <module>
    from IPython.core.profiledir import ProfileDir
  File "C:\Users\lenovo\AppData\Local\Programs\Python\Python37\lib\site-packages\IPython\__init__.py", line 54, in <module>
    from .core.application import Application
  File "C:\Users\lenovo\AppData\Local\Programs\Python\Python37\lib\site-packages\IPython\core\application.py", line 25, in <module>
    from IPython.core import release, crashhandler
  File "C:\Users\lenovo\AppData\Local\Programs\Python\Python37\lib\site-packages\IPython\core\crashhandler.py", line 27, in <module>
    from IPython.core import ultratb
  File "C:\Users\lenovo\AppData\Local\Programs\Python\Python37\lib\site-packages\IPython\core\ultratb.py", line 115, in <module>
    from IPython.core import debugger
  File "C:\Users\lenovo\AppData\Local\Programs\Python\Python37\lib\site-packages\IPython\core\debugger.py", line 47, in <module>
    from pdb import Pdb as OldPdb
  File "C:\Users\lenovo\AppData\Local\Programs\Python\Python37\lib\pdb.py", line 76, in <module>
    import code
  File "C:\Users\lenovo\Desktop\HW1_Q1\code.py", line 5, in <module>
    "execution_count": null,
NameError: name 'null' is not defined
[W 00:23:56.368 NotebookApp] KernelRestarter: restart failed
[W 00:23:56.368 NotebookApp] Kernel 3087f4f8-f452-476b-becc-41f53a23cf80 died, removing from map.