TypeError on built-ins when using keyword arguments is not found #5771

Bug Report

Many (most?) built-ins do not take keyword arguments (see Python issue 8706). Nevertheless, mypy does not report about the corresponding TypeError raised at runtime.

To Reproduce

1. use a built-in method, e.g. get(), with a keyword argument
2. run mypy, don't get an error
3. run the program, get a TypeError

MWE:

my_dict = dict(a=1)
a_value = my_dict.get('b', default='nothing to find')
print(a_value)

$ mypy tst.py
Success: no issues found in 1 source file
$ python tst.py
Traceback (most recent call last):
  File "/opt/data/UserWork/hintze/my_work/tst.py", line 2, in <module>
    a_value = my_dict.get('b', default='nothing to find')
TypeError: dict.get() takes no keyword arguments

Expected Behavior

I thought mypy would tell me about the TypeError...

Actual Behavior

...but it didn't.

Your Environment

• Mypy version used: 0.901
• Mypy command-line flags: None
• Mypy configuration options from mypy.ini (and other config files): None
• Python version used: Python 3.9.1
• Operating system and version: [GCC 4.8.5 20150623 (Red Hat 4.8.5-44)] on linux