def add(x: int, y: int):
return x + y
first = 19
second = 23
result: str = first + second
#result: str = add(first, second)
$ mypy variable_and_function.py
variable_and_function.py:7:15: error: Incompatible types in assignment (expression has type "int", variable has type "str") [assignment]
Found 1 error in 1 file (checked 1 source file)
$ mypy --strict variable_and_function.py
variable_and_function.py:2:1: error: Function is missing a return type annotation [no-untyped-def]
Found 1 error in 1 file (checked 1 source file)