It's normally discouraged as it detracts from readability, from PEP8:
Compound statements (multiple statements on the same line) are
generally discouraged.
Yes:
if foo == 'blah':
do_blah_thing()
do_one()
do_two()
do_three()
Rather not:
if foo == 'blah': do_blah_thing()
do_one(); do_two(); do_three()
While sometimes it's okay to put an if/for/while with a small body on
the same line, never do this for multi-clause statements. Also avoid
folding such long lines!
Rather not:
if foo == 'blah': do_blah_thing()
for x in lst: total += x
while t < 10: t = delay()
Definitely not:
if foo == 'blah': do_blah_thing()
else: do_non_blah_thing()
try: something()
finally: cleanup()
do_one(); do_two(); do_three(long, argument,
list, like, this)
if foo == 'blah': one(); two(); three()