DB<1> x $period 0 Date::Set=HASH(0x5ef384) 'dtstart' => undef 'fixtype' => 1 'list' => ARRAY(0x1131ac) 0 HASH(0x606130) 'a' => Date::Set::ICal=HASH(0x605d94) 'epoch' => 20021201 'b' => Date::Set::ICal=HASH(0x497a74) 'epoch' => 20021231 'open_begin' => 0 'open_end' => 0 'tolerance' => 0 'type' => 'Date::Set::ICal' 'wkst' => 'MO'