title: Can't run jupyter notebook command in conda environment
body: <p>I am getting this error when I try to run <code>jupyter notebook</code> after activating an environment. Should I install <code>ipykernel</code> in the environment? I have already installed <code>nb_conda</code> in base. I don't face this issue when running <code>jupyter notebook</code> normally.</p>
  <p><a href="https://i.stack.imgur.com/hgKlw.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/hgKlw.png" alt="unable to run jupyter notebook in conda envoronment" /></a></p>
  <p>I created the environment by running <code>conda create -n env_name python=3.7.1</code> and then ran <code>pip install -r requirements.txt</code>. These are the requirements installed:</p>
  <img src="https://i.stack.imgur.com/x7nbZ.png" width="250"/>