#1st_class__1stclas__first_class__firstclas__first-class_mail__firstclassmail__1st-class_mail__1stclassmail__priority_mail  mail that includes letters and postcards and packages sealed against inspection
  supertype:  mail  the bags of letters and packages that are transported by the postal service
  subtype:  correspondence.1st_class__correspondence  communication by exchange of letters

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