Return a definition

[deanhystad]

user_input is a string, so str(user_input) does nothing. I don't understand what you are doing with the parenthesis in this line:

# return ('The definition of') ,user_input + (glossary [user_input])
return 'The definition of ' + user_input + ' is ' + glossary [user_input]

I think a format string is a better solution (f'' or ''.format()), but you can use string concatenation if you want.