python-shell-unbuffered

python-shell-unbuffered is a variable defined in `python.el'.
Its value is

t

• This variable is safe as a file local variable if its value
  satisfies the predicate `booleanp'.

Documentation:
Should shell output be unbuffered?.
When non-nil, this may prevent delayed and missing output in the
Python shell. See commentary for details.

You can customize this variable.