python tip

Let's say we have a list with main colors red, green, and blue. And somewhere in our code we have a new variable that contains some color, so here c = red. Then we want to check if this is a color from our main colors. We could of course check this against each item in our list like so:

colors = ["red", "green", "blue"]

c = "red"

# cumbersome and error-prone
if c == "red" or c == "green" or c == "blue":
    print("is main color")

But this can become very cumbersome, and we can easily make mistakes, for example if we have a typo here for red. Much simpler and much better is just to use the syntax if x in list:

colors = ["red", "green", "blue"]

c = "red"

# better:
if c in colors:
    print("is main color")