for the input of 7,1
the range should be (1,1) and (7,7)
input 1,7,2 ---> output (1,2) (7,7)
input 1,7,2,3 ---> output (1,3) (7,7)
input 1,7,2,3,4 ---> output (1,4)(7,7)
input 1,7,2,3,4,9 ---> output (1,4)(7,7)(9,9)
input 1,7,2,3,4,9,8 ---> output (1,4)(7,9)
input 1,7,2,3,4,9,8,5 ---> output (1,5)(7,9)
input 1,7,2,3,4,9,8,5,6---> output (1,9)

def inRange(i):
   for first,second in ranges.copy().items():
     if i in range(first,second+1):
       return True
     elif i > first and second+1 == i:
       ranges[first] = i
       return True
     elif i < first and i+1 == first:
       ranges[i] = second
   del ranges[first]
       return True
   return False

    input = [7,1,2,6,4,8]
    ranges = {}
    for i in input:
      if not ranges or not inRange(i):
        ranges[i] = i
    print(ranges)

{1: 2, 6: 8, 4: 4}

{1: 3, 6: 8, 4: 4}