I don't know list, I not good at list.

[MRAB]

 > I've been beating my head against the desk trying to figure out a
 > method to accomplish this:
 >
 > Take a list (this example is 5 items, It could be 150 or more - i.e.
 > it's variable length depending on the city/local calling zones)
 >
 > The first 6 digits of phone numbers(NPA/NXX) in a local calling area.
 > I want to concatenate the last digit for insertion into a call
 > routing pattern.
 >
 > I tried this and failed miserably:
 >
 > list1=['252205','252246','252206','252247','252248']
 > for item in list1:
 >         try:
 >                 item1=list1[0]
 >                 item2=list1[1]
 >                 if item1[0:5] == item2[0:5]:
 >                         print item1[0:5] + '[' + item1[5:6] + 
item2[5:6] + ']'
 >                         list1.pop(0)
 >                 else:
 >                         print item1
 >                         list1.pop(0)
 >         except:
 >                 try:
 >                         print item1
 >                         list1.pop(0)
 >                 except:
 >                         pass
 >
 > #-----------------------------------------------------------------
 > My intent is to have the end data come out (from the example list
 > above) in the format of
 > 25220[56]
 > 25224[678]
 >
 > I tried putting together a variable inserted into a regular
 > expression, and it doesn't seem to like:
 > Item1=list1[0]
 > Itemreg = re.compile(Item1[0:5])
 > For stuff in itemreg.list1:
 >         #do something
 >
 > Can somebody throw me a bone, code example or module to read on
 > python.org? I'm a n00b, so I'm still trying to understand functions
 > and classes.
 >
 > I thought the experts on this list might take pity on my pathetic
 > code skillz!
 >
defaultdict comes in handy:

 >>> list1 = ['252205','252246','252206','252247','252248']
 >>> from collections import defaultdict
 >>> d = defaultdict(set)
 >>> for item in list1:
	d[item[ : 5]].add(item[5 : ])


 >>> d
defaultdict(<class 'set'>, {'25224': {'8', '7', '6'}, '25220': {'5', '6'}})
 >>> for k, v in d.items():
	print(k + "[" + "".join(v) + "]")

	
25224[876]
25220[56]