#mid-September  the middle part of September
  supertype:  #time_period__period__period_of_time  an amount of time; "a time period of 30 years"; "hastened the period of his recovery"
  part of:  #September__Sep__Sept  the month following August and preceding October
     part of:  #Gregorian_calendar__New_Style  the solar calendar now in general use, introduced by Pope Gregory XIII in 1582 AD to correct an error in the Julian calendar by suppressing 10 days, making Oct 5 be called Oct 15, and providing that only centenary years divisible by 400 should be leap years; it was adopted by Great Britain and the American colonies in 1752
     part of:  #autumn__fall  the season when the leaves fall from the trees; "in the fall of 1973"

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