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Ironically, the first thing we’re going to do is show how to tell a computer to ignore a part of a program. Text written in a program but not run by the computer is called a comment. Python interprets anything after a # as a comment.

Comments can:

  • Provide context for why something is written the way it is:

    # This variable will be used to count the number of times anyone tweets the word persnickety persnickety_count = 0
  • Help other people reading the code understand it faster:

    # This code will calculate the likelihood that it will rain tomorrow complicated_rain_calculation_for_tomorrow()
  • Ignore a line of code and see how a program will run without it:

    # useful_value = old_sloppy_code() useful_value = new_clean_code()



Documentation is an important step in programming. Write a comment describing the first program you want to write!

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