Python's variables are not buckets that contain objects; they're pointers. Assignment statements don't copy: they point a variable to a value (and multiple variables can "point" to the same value).| www.pythonmorsels.com
Assignment in Python might surprise you. How do names and values work? This presentation explains it all.| nedbatchelder.com
Equality checks whether two objects represent the same value. Identity checks whether two variables point to the same object.| www.pythonmorsels.com
An iterable is anything you're able to iterate over (iter-able). Iterables can be looped over and anything you can loop over is an iterable. Not every iterable is indexable or has a length.| www.pythonmorsels.com