Provide a class Letter() for authoring a simple letter. In the constructor, supply the names of the sender and the recipient: def __init__(self, letterFrom, letterTo)Supply a method def addLine (self, line) to add a line of text to the body of the letter. Supply a method def getText(self)that returns the entire text of the letter. You also need to implement a test file to test your Letter(). The letter should have the following form: Dear recipient name: "blank line"first line of the body second line of the body last line of the body "blank line" Sincerely, "blank line" sender name For example, assuming that you have the sender named John and the recipient named Mary. John wrote two lines of the letter: 1: "How are you?" 2: I really miss you! Your test file leveraging Letter() will have the following output: Dear Mary: How are you? I really miss you! Sincerely, John