One reason to use functions is to reduce code duplication

Programmers rarely define their own functions.

A function may only be called at one place in a program.

Information can be passed into a function through parameters.

Every Python function returns some value.

In Python, some parameters are passed by reference.

In Python, a function can return only one value.

Python functions can never modify a parameter.

One reason to use functions is to reduce code duplication.

Variables defined in a function are local to that function.

It's a bad idea to define new functions if it makes a program longer.

Write and test a function to meet this specification. squareEach (nums) nums is a list of numbers. Modifies the list by squaring each entr

Write and test a function to meet this specification. sumList (nums) nums is a list of numbers. Returns the sum of the numbers in the list.

Write and test a function to meet this specification. toNumbers (strList) strList is a list of strings, each of which represents a number. Modifies each entry in the list by converting it to a number.

Use the functions from the previous three problems to implement a program that computes the sum of the squares of numbers read from a file. Your program should prompt for a file name and print out the sum of the squares of the values in the file. Hint: Use readlines ()

Write and test a function to meet this specification. drawFace (center, size, win) center is a Point, size is an int, and win is a GraphWin. Draws a simple face of the given size in win. Your function can draw a simple smiley (or grim) face. Demonstrate the function by writing a program that draws several faces of varying size in a single window.

Use your drawFace function from the previous exercise to write a photo anonymizer. This program allows a user to load an image file (such as a PPM or GIF) and to draw cartoon faces over the top of existing faces in the photo. The user first inputs the name of the file containing the image. The image is displayed and the user is asked how many faces are to be blocked. The program then enters a loop for the user to click on two points for each face: the center and somewhere on the edge of the face (to determine the size of the face). The program should then draw a face in that location using the drawFace function. Hints: Section 4.8.4 describes the image-manipulation methods in the graphics library. Display the image centered in a GraphWin that is the same width and height as the image, and draw the graphics into this window. You can use a screen capture utility to save the resulting images.

Write a function to meet this specification. move To (shape, newCenter) shape is a graphics object that supports the getCenter method and newCenter is a Point. Moves shape so that newCenter is its center. Use your function to write a program that draws a circle and then allows the user to click the window 10 times. Each time the user clicks, the circle is moved where the user clicked.