One of the simplest methods is method one and method three, because they only need to call related functions.
The first method, with the help of the non-repeatable characteristics of elements in the set, first converts the list into a set, and then returns the set to the list, so that the repeated elements can be removed; In the third method, you can also use the Unique () method in Numpy to delete duplicate elements. At the same time, note that the element return type is ndarray, so it needs to be converted to list. If students are interested in Method 2, they can also reproduce it manually. It is a little more difficult than method 1 and method 3, but it is more conducive to training code thinking.