Pandas find matching sub-strings and split on them

Question

I have a pandas column that looks like this:

0                         LOT 8 BLK 32 MISSIONARY HEIGHTS 
1                          LTS 31-39 & PT 30, 15-22 LEWIS 
2                                          LT 2 DEPOT SUB
....

I want to extract out the lot number from this but sometimes they are spelled "LOT", "LTS" or "LT". And I want to extract out the lot number into a new column. So, for the example above, I would have:

         df['Lot']
0             8
1           31-39
2             2

How can I do this? Please advise.