will automatically separate them with single space enter the following into the interactive shellprint('cats''dogs''mice'cats dogs mice but you could replace the default separating string by passing the sep keyword argument different string enter the following into the interactive shellprint('cats''dogs''mice'sep=','cats,dogs,mice you can add keyword arguments to the functions you write as wellbut first you'll have to learn about the list and dictionary data types in the next two for nowjust know that some functions have optional keyword arguments that can be specified when the function is called the call stack imagine that you have meandering conversation with someone you talk about your friend alicewhich then reminds you of story about your coworker bobbut first you have to explain something about your cousin carol you finish you story about carol and go back to talking about boband when you finish your story about bobyou go back to talking about alice but then you are reminded about your brother davidso you tell story about himand then get back to finishing your original story about alice your conversation followed stack-like structurelike in figure - the conversation is stack-like because the current topic is always at the top of the stack carol alice bob bob bob alice alice alice david alice alice alice figure - your meandering conversation stack similar to our meandering conversationcalling function doesn' send the execution on one-way trip to the top of function python will remember which line of code called the function so that the execution can return there when it encounters return statement if that original function called other functionsthe execution would return to those function calls firstbefore returning from the original function call functions