[thing for thing in list_of_things]
>>> x = [1, 2, 3, 4, 5]
>>> y = [2*a for a in x if a % 2 == 1]
>>> print(y)
[2, 6, 10]
to_db = [(i['col1'], i['col2']) for i in dr]
exec("try:
if sam[0] != 'harry':
print('hello', sam)
except: pass")