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Exercise

Measuring time II

As we discussed in the lectures, in the majority of cases, a list comprehension is faster than a for loop.

In this demonstration, you will see a case where a list comprehension and a for loop have so small difference in efficiency that choosing either method will perform this simple task instantly.

In the list words, there are random words downloaded from the Internet. We are interested to create another list called listlet in which we only keep the words that start with the letter b.

In case you are not familiar with dealing with strings in Python, each string has the .startswith() attribute, which returns a True/False statement whether the string starts with a specific letter/phrase or not.

Instructions 1/2

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  • Assign the time before the execution of the list comprehension
  • Assign the time after the execution of the list comprehension