"command not found" when the tool was installed via pip

When using python as matlab like tool.  jupyter or voila are necessary to be installed via pip.
be reminded that if the OS is linux, the tolls which are installed via pip (or pip3) are stored in "~/.local/bin"
so you need to add the path.
for example edit .bashrc

  PATH="$HOME/.local/bin:$PATH"

I am using WSL and noticed that it's default ~/.profile has the bellow line

if [ -d "$HOME/.local/bin" ] ; then
    PATH="$HOME/.local/bin:$PATH"
fi

it means when bash is loaded, it checks if there is .local/bin, if so add the directory to the PATH, if not don't do anything.
My .local was created first time after using pip. so the Path was not set.
so without restart the terminal,

$source ~/.profile

would also  add pip toll path