We can many submodules inside a module. A directory with a __init__.py can also be used a module and all .py files inside it become submodules.

$ tree mymodule
mymodule
|-- bars.py
|-- __init__.py
`-- utils.py

In this example mymodule is the module name and bars and utils are two submodules in it. You can create an empty __init__.py using touch command.

$ touch mymodule/__init__.py