#### Ohms Law

```# https://en.wikipedia.org/wiki/Ohm%27s_law
from __future__ import annotations

def ohms_law(voltage: float, current: float, resistance: float) -> dict[str, float]:
"""
Apply Ohm's Law, on any two given electrical values, which can be voltage, current,
and resistance, and then in a Python dict return name/value pair of the zero value.

>>> ohms_law(voltage=10, resistance=5, current=0)
{'current': 2.0}
>>> ohms_law(voltage=0, current=0, resistance=10)
Traceback (most recent call last):
...
ValueError: One and only one argument must be 0
>>> ohms_law(voltage=0, current=1, resistance=-2)
Traceback (most recent call last):
...
ValueError: Resistance cannot be negative
>>> ohms_law(resistance=0, voltage=-10, current=1)
{'resistance': -10.0}
>>> ohms_law(voltage=0, current=-1.5, resistance=2)
{'voltage': -3.0}
"""
if (voltage, current, resistance).count(0) != 1:
raise ValueError("One and only one argument must be 0")
if resistance < 0:
raise ValueError("Resistance cannot be negative")
if voltage == 0:
return {"voltage": float(current * resistance)}
elif current == 0:
return {"current": voltage / resistance}
elif resistance == 0:
return {"resistance": voltage / current}
else:
raise ValueError("Exactly one argument must be 0")

if __name__ == "__main__":
import doctest

doctest.testmod()
```  