Huge terminal game (in development)

I'm developing a big (for me, as a beginner) terminal program "Brainfuck - The Game", in which you have to complete Brainfuck challenges. I would like your review on existing code (and project structuring) before I continue to expand it even more.

main.py

""" Brainfuck - the game. """

def main ():
    """ The main function. """
    print ("Type 'help' for a list of supported commands.")
    # Every command is a seperate method & has full access to shared class
    shared = m_shared.Shared()
    commands = { "help" : m_help.help,
                 "exit" : m_exit.exit }
    # The loop
    while shared.is_running:
        commands[shared.prompt_command(shared.COMMANDS)](shared)

if __name__ == "__main__":
    # Here and further on "m_" stands for "module"
    import m_shared
    import m_help
    import m_exit
    main()

m_shared.py

```
""" A module that contains Shared class. """

import m_statscontainer

class Shared (object):
""" Holds everything that's shared among command functions. """

# Subclasses that help to divide this huge class into some smaller chunks
stats_container = m_statscontainer.Stats_Container()

# Constants
COMMANDS = ["help", "exit", "run", "open", "save", "setcell", "def",
"code", "limit", "del", "edit", "reset", "debug", "memo",
"brainfuck", "challenge", "random", "stats", "credits"]
DEFAULT_STEP_LIMIT = 10000 # Protects program from infinite loops

# Variables
is_running = True
last_input = []
# Variables for the brainfuck program
limit = DEFAULT_STEP_LIMIT
memory_world = {}
definitions = {}
code = []
compiled_code = []

# Methods
def __init__(self):
""" Initializes the Shared class. """
pass

def prompt_command(self, valid_commands):
""" Repeatedly prompts input unitl valid command can be returned. """
user_input = []
while user_input == [] or user_input[0] not in valid_commands:

I have a few minor comments, like "move the import statements to the top", but my biggest concern is the confusing structure. Why do you need a class? A warning sign that something isn't a class, or shouldn't be a class, is a class with two methods, one of which is __init__. Your init is even empty. Okay, your class has three methods, but I'd still count that.

Why do you need so many modules? The most worrying example of this is, I think, m_exit.py. If you start writing modules for a single two-line function, there's something wrong.

StackExchange Code Review Q#86595, answer score: 3