Phew.
You've now seen
some of the subtleties of passing parameters,
accessing global variables, don't do it,
functions calling other functions,
and functions having side effects.
You should now be able to,
avoid the use of global variables and function definitions
by creating formal parameters for all values that are needed,
and you should be able to identify whether a function has any side effects,
including mutations to lists and dictionaries.
As much as possible, I encourage you to avoid side effects,
come as close to strict functional programming as you can.
Speaking of functional programming,
why did the functional program returned her TV?
Because she kept muting the sound by accident,
she returned the TV and asked for one that was immutable.
Okay. That one was a stretch. We'll see you next time.