Sure, here's a Python version of this equation written as a function and a usage example:
```python
# math or similar library reqired for square root and power operations
import math

def car_touching_planet_length(car_clearance_meters, planet_radius_meters):
    wheel_distance = 2*math.sqrt(2 * planet_radius_meters * car_clearance_meters - math.pow(car_clearance_meters, 2))
    return wheel_distance

# Example usage:
try: 
    earth_radius = 6371e3
    average_sedan_clearance = 150e-3
    earth_car_touching_planet_lenght = car_touching_planet_length(average_sedan_clearance, earth_radius)
    car_rounded = round(earth_car_touching_planet_lenght,2)
    print(f"Length of a car touching earth because of the planet curvature is about {car_rounded} meters")
except ValueError as e:
    print(e)
```
spam fails_task lang_mismatch pii not_appropriate hate_speech sexual_content quality toxicity humor helpfulness creativity violence