user: Question: How many winners from previous round were there in the Semi finals?
Columns: ['Round', 'Clubs remaining', 'Clubs involved', 'Winners from previous round', 'New entries this round', 'Leagues entering at this round']
Types: ['text', 'real', 'real', 'text', 'text', 'text']
Sample row: ['Preliminary round', 123.0, 22.0, 'none', '22', 'Levels 4 and 5 in football league pyramid']
SQL:

assistant: SELECT SUM("Winners from previous round") FROM "Table" WHERE "Round" = 'Semi finals';