easy questions from python newbie

[walterbyrd]

This is the first real python program I have ever worked on. What I
want to do is:
1) count identical records in a cvs file
2) create a new file with quantities instead duplicate records
3) open the new file in ms-excel

For example, I will start with a file like:

1001
1012
1008
1012
1001
1001

and finish with a file like:

1001,3
1008,1
1012,2

What I need to know:
1) is there a function in python that will sort a file into another
file. Something like:
sort file1.txt > file2.txt from the DOS command line. I know there is
also a similar "sort" funtion in Unix.
2) is there a function in python that will correctly load a csv file
into an excel spreadsheet,
and open that spreadsheet.
3) I will probably be working with 50 items, or less, would it be best
for me to do this with a
multi-diminsional array? For example: sort the file, read a rec into
the array, if the next rec is the same then incr the count, otherwise
add a new rec with a count of 1. Then write the array to a file?