def get_cfg_option(cfg, sec, opt, verbose=False):
    """
    Retrieve value of a specific option of a configuration.

    Parameters
    ----------
    cfg : configparser.ConfigParser()
        Configuration as retrieved by the function read_cfg_file().
    sec : str
        The section in which the option is located.
    opt : str
        The option that should be retrieved.
    verbose : bool, optional
        Print info, if either section or option could not be found in cfg.

    Returns
    -------
    str
        Value of the option
    """
    if sec not in cfg:
        verbose and print("Section '%s' is not in configuration '%s'"
                          % (sec, cfg))
        return None

    if opt not in cfg[sec]:
        verbose and print("Option '%s' is not in section '%s'"
                          % (opt, sec))
        return None

    option = cfg[sec][opt]

    return option