def dict_to_string(m: dict) -> dict:
    """Convert dict values to strings

    Parameters
    ----------
    m : dict

    Returns
    -------
    dict
    """
    for k, v in m.items():
        if isinstance(v, dict):
            m[k] = dict_to_string(v)
        else:
            m[k] = str(v)

    return m