Comment by riazrizvi

The titles are oddly worded. For example -

  Collection Access and Iteration
  How fast can you get data out of Python’s built-in collections? Here is a dramatic example of how much faster the correct data structure is. item in set or item in dict is 200x faster than item in list for just 1,000 items!

It seems to suggest an iteration for x in mylist is 200x slower than for x in myset. It’s the membership test that is much slower. Not the iteration. (Also for x in mydict is an iteration over keys not values, and so isn’t what we think of as an iteration on a dict’s ‘data’).

Also the overall title “Python Numbers Every Programmer Should Know” starts with 20 numbers that are merely interesting.

That all said, the formatting is nice and engaging.