Check argument types [arg-type]

Mypy checks that argument types in a call match the declared argumenttypes in the signature of the called function (if one exists).

Example:

from typing import List, Optional
 
def first(x: List[int]) -> Optional[int]:
     return x[0] if x else 0
 
t = (5, 4)
# Error: Argument 1 to "first" has incompatible type "Tuple[int, int]";
#        expected "List[int]"  [arg-type]
print(first(t))