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Python Python Basics (2015) Python Data Types Splitting and Joining


He pulled the .format() function out of no where and I just lost it after that. also what is the {} for when he does that line of code towards the end using the .format() function?

1 Answer

Steven Parker
Steven Parker
221,309 Points

The {} symbols are the "placeholder".

Those symbols indicate the place in the template string where the format function will put the argument it is given. For example:

name = "Python"
guess = "{} is fun to use.".format(name)
print(guess)  # this will show: "Python is fun to use."

Can you explain what happened in this line of code from the video? "My favorite flavors are: {}".format(", ".join(flavors))

Steven Parker
Steven Parker
221,309 Points

Ok, I'll break it down into steps:

  • at the start, flavors is a list of 3 strings: ['chocolate', 'mint', 'strawberry']
  • ", ".join(flavors) :point_left: this converts the list into one string: 'chocolate, mint, strawberry'
  • "My favorite flavors are: {}".format(:arrow_up:) :point_left: this puts the new string in place of the {}
  • 'My favorite flavors are: chocolate, mint, strawberry' :point_left: so this is the final result