Processes practice ps command not working properly

[tudorcondrea]

Hello, in the Processes subsection where we open 10 sleep processes, the ps -e -H -o pid,ppid,cmd | (head -1; grep "python3 sleepy_creator.py") and ps -e -H -o pid,ppid,cmd | (head -1; grep sleep) do not show the list of processes, however running ps -e -H is sufficient