key value if len and key in key else FOO try key except IndexError Key

# x = [{'key':'value'}]

#1:

if len(x) and 'key' in x[0]:
    b = x[0]['key']
else:
    b = FOO

#2:
try:
    b = x[0]['key']
except (IndexError, KeyError):
    b = FOO