Python script: Removing tabs, separating columns with comma, listing max/min

Python script: Removing tabs, separating columns with comma, listing max/min

I am trying to write a script in Python to remove tabs/blank spaces
between two columns (one with x coordinates, the other with y coordinates)
plus separate columns by a comma instead and list the maximum and minimum
values of each column (2 values for each the x and y coordinates) at the
end like this:
10000000 6000000
20000000 6100000
30000000 6200000
40000000 6300000
50000000 6400000
to appear like:
10000000,6000000
20000000,6100000
30000000,6200000
40000000,6300000
50000000,6400000
10000000 50000000 60000000 640000000
I'm a novice so any help wis v much appreciated. Many thanks!