def METHOD_NAME(self, vg):
    '''
    Checks VG existence by name or UUID. It removes the '/dev/' prefix before checking.
    :param vg: A string with the name or UUID of the VG.
    :returns: A boolean indicates whether the VG exists or not.
    '''
    vg_found = False
    dev_prefix = '/dev/'
    if vg.startswith(dev_prefix):
        vg_id = vg[len(dev_prefix):]
    else:
        vg_id = vg
    vg_found = vg_id in self.vg_list
    return vg_found