def set_bypass(bypass_type=None):
    """Set bypass flag for each fire module in SqueezeNet architecture.

    Parameters
    ----------
    bypass_type : {None, 'simple', 'complex'}
        Bypass type to be applied, see Fig. 2 [1] for more detail.

    Returns
    -------
    bypass : dict
        Dictionary of bypass values for each fire module, e.g.,
        if bypass['fire1'] is True then bypass is applied to fire module 1,
        see Fig. 2 [1] for more detail.

    """
    bypass = {'fire1': False, 'fire2': False, 'fire3': False, 'fire4': False,
              'fire5': False, 'fire6': False, 'fire7': False, 'fire8': False,
              'fire9': False}
    if bypass_type in ['simple', 'complex']:
        bypass['fire3'] = True
        bypass['fire5'] = True
        bypass['fire7'] = True
        bypass['fire9'] = True

    if bypass_type == 'complex':
        bypass['fire2'] = True
        bypass['fire4'] = True
        bypass['fire6'] = True
        bypass['fire8'] = True

    return bypass