user: Question: I want the NGC number for Leo of Irregular galaxy
Columns: ['NGC number', 'Object type', 'Constellation', 'Right ascension ( J2000 )', 'Declination ( J2000 )']
Types: ['real', 'text', 'text', 'text', 'text']
Sample row: [2903.0, 'Spiral galaxy', 'Leo', '09h32m09.7s', '°30′03″']
SQL:

assistant: SELECT "NGC number" FROM "Table" WHERE "Constellation" = 'Leo' AND "Object type" = 'Irregular galaxy';