def length_converter():
print("\nLength Converter")
units = {"1": "meters", "2": "kilometers", "3": "miles", "4": "centimeters"}
for key, value in units.items():
print(f"{key}. {value.capitalize()}")
from_unit = input("Convert from (1-4): ")
to_unit = input("Convert to (1-4): ")
if from_unit in units and to_unit in units: