Commenting on Python : I am a student taking my first Python class and am using Anaconda & Jupyter for Python 3. I have read up on commenting and understand they begin with a hash mark ( # ) and whitespace character and continue to the end of the line. It is my understanding that they should not affect the execution of the code. 

When I run "ls" in order to display my working directory it runs perfectly fine. However, when I add a comment just above it, it does not run. Can someone please help me understand why this might be? Pictures attached. 

This is the error I receive with a comment: **---------------------------------------------------------------------------
NameError                                 Traceback (most recent call last)
<ipython-input-9-96a2904231e9> in <module>()
      1 # show working directory
----> 2 ls
NameError: name 'ls' is not defined**


![run 1] https://i.stack.imgur.com/tS4aW.png
! [run 2] https://i.stack.imgur.com/fYegx.png