Rearranging elements in Python

[Nirmal]

i am new to Python and i cant get this.I have a List and i want to take the input from there and write those in files .

p = ['Eth1/1', 'Eth1/5','Eth2/1', 'Eth2/4','Eth101/1/1', 'Eth101/1/2', 'Eth101/1/3','Eth102/1/1', 'Eth102/1/2', 'Eth102/1/3','Eth103/1/1', 'Eth103/1/2', 'Eth103/1/3','Eth103/1/4','Eth104/1/1', 'Eth104/1/2', 'Eth104/1/3','Eth104/1/4']

What i am trying :

with open("abc1.txt", "w+") as fw1, open("abc2.txt", "w+") as fw2:
for i in p:
    if len(i.partition("/")[0]) == 4:
        fw1.write('int ' + i + '\n  mode\n')
    else:
        i = 0
        while i < len(p):
            start = p[i].split('/')
            if (start[0] == 'Eth101'):
                i += 3

            key = start[0]
            i += 1
            while i < len(p) and p[i].split('/')[0] == key:
                i += 1
            end = p[i-1].split('/')
            fw2.write('confi ' + start[0] + '/' + start[1] + '-' + end[1] + '\n mode\n')

What i am looking for :

abc1.txt should have

int Eth1/1
  mode
int Eth1/5
  mode
int Eth2/1
  mode
int Eth 2/4
  mode

abc2.txt should have :

int Eth101/1/1-3
  mode
int Eth102/1/1-3
  mode
int Eth103/1/1-4
  mode
int Eth104/1/1-4
  mode

1. So any Eth having 1 digit before " / " ( e:g Eth1/1 or Eth2/2 )should be in one file that is abc1.txt .
   

1. Any Eth having 3 digit before " / " ( e:g Eth101/1/1 or Eth 102/1/1 ) should be in another file that is abc2.txt and .As these are in ranges , need to write it like Eth101/1/1-3, Eth102/1/1-3 etc
   

Any Idea ?