The FilterByValue function is a method defined on the HashMap type. It generates a new HashMap
containing only the elements that satisfy a specified condition,
as determined by a predicate function applied to each element's value.
Note: Will add later doc
* fix: use loop to get value . On Get() and Contains()
* fix: Use reflect. DeepEqual() determines whether the keys are equal
* feat: add CopyOnWriteList. A thread-safe list.
* fix: fix failed unit test
* feat: add Equal() in CopyOnWriteList.
fix: update some function`s names
* doc: add copyonwritelist.md and copyonwritelist_zh-CN.md
