import java.util.Collection;

Package is a mechanism to group related classes ,interfaces and enums
in to a single module.
Package can be declared using the following statement :
Syntax : package <package-name>
Coding Convention : package name should be declared in small letters.
package statement defines the namespace.
The main use of package is
1) To resolve naming conflicts
2) For visibility control : We can define classes and interfaces that are
not accessible outside the class

If you use a package declaration, it must be the first thing in your Java file,
and the import declarations must be put immediately after it.

import random.library.*;