see your Python code run, line by line. Runs in your browser; nothing is sent to a server.
GitHub
➜ just ran ➜ runs next
Print output

  


  

  

    

      
        
        
      
      
      
      
      
      
      
      
    

    

      

        

          What happened
          
        

        

      

    

    

      
Loading Python…
First visit downloads about 10 MB; after that it's cached.