import importlib.util
import os

def get_module_size(module_name):
    """Get the total number of bytes in the cached .pyc file or .py file of a module or package.

    Args:
        module_name (str): The name of the module or package.

    Returns:
        int: The total number of bytes in the cached .pyc file or .py file.
    """
    spec = importlib.util.find_spec(module_name)

    if spec is not None and spec.has_location:
        # If the module is found and has a location, check for .pyc file first
        pyc_file_path = spec.origin + 'c'
        if os.path.exists(pyc_file_path):
            return os.stat(pyc_file_path).st_size
        else:
            # If .pyc file doesn't exist, check for .py file
            py_file_path = spec.origin
            if os.path.exists(py_file_path):
                return os.stat(py_file_path).st_size

    return 0  # Return 0 if no .pyc or .py file found


import sys

def get_total_module_size():
    """Get the total number of bytes for all modules listed in sys.modules.

    Returns:
        int: The total number of bytes for all modules.
    """
    total_size = 0
    for module_name in sys.modules:
        module_size = get_module_size(module_name)
        total_size += module_size

    return total_size

if __name__ == '__main__' and __package__ is None:
    __spec__ = importlib.util.spec_from_file_location('__main__', __file__)
total_size = get_total_module_size()
print("Total size of all modules in sys.modules: {} bytes".format(total_size))