In Python, Assignment statements do not copy objects, they create bindings between a target and an object. When we use = operator user thinks that this creates a new object; well, it doesn’t. It only creates a new variable that shares the reference of the original object. Sometimes a user wants to work with mutable objects, in order to do that user looks for a way to create “real copies” or “clones” of these objects. Or, sometimes a user wants copies that user can modify without automatically modifying the original at the same time, in order to do that we create copies of objects. A copy is sometimes needed so one can change one copy without changing the other. In Python, there are two ways to create copies : Deep copy Shallow copy In order to make these copy, we use copy module. We use copy module for shallow and deep copy operations. For Example filter_none