What does '->' mean in python? : <p>All,</p>

<p>Can you please tell me what this line means in Python?  I don't know if I'm using it properly.  </p>

<p>def read_places_file(filename) -> List[PlaceInformation]: </p>

<p>We are defining a method that takes a parameter called, 'filename'.  And then what does the rest of the line mean?  What does the '->' operator mean?  </p>

<p>Thank you very much in advance.  </p>
