[mypy] fix small folders (#4292)

* add final else-statement

* fix file_transfer

* fix quantum folder

* fix divide_and_conquer-folder

* Update build.yml

* updating DIRECTORY.md

* Update ripple_adder_classic.py

* Update .github/workflows/build.yml

* removed imports from typing

* removed conversion to string

* Revert "removed conversion to string"

This reverts commit 2f7c4731d1.

* implemented suggested changes

* Update receive_file.py

Co-authored-by: github-actions <${GITHUB_ACTOR}@users.noreply.github.com>
Co-authored-by: Christian Clauss <cclauss@me.com>

electronics/electric_power.py

@@ -42,6 +42,8 @@ def electric_power(voltage: float, current: float, power: float) -> Tuple:
         return result("current", power / voltage)
     elif power == 0:
         return result("power", float(round(abs(voltage * current), 2)))
+    else:
+        raise ValueError("Exactly one argument must be 0")
 
 
 if __name__ == "__main__":

electronics/ohms_law.py

@@ -32,6 +32,8 @@ def ohms_law(voltage: float, current: float, resistance: float) -> Dict[str, flo
         return {"current": voltage / resistance}
     elif resistance == 0:
         return {"resistance": voltage / current}
+    else:
+        raise ValueError("Exactly one argument must be 0")
 
 
 if __name__ == "__main__":