#### Speed Conversions

A
```"""
Convert speed units

https://en.wikipedia.org/wiki/Kilometres_per_hour
https://en.wikipedia.org/wiki/Miles_per_hour
https://en.wikipedia.org/wiki/Knot_(unit)
https://en.wikipedia.org/wiki/Metre_per_second
"""

speed_chart: dict[str, float] = {
"km/h": 1.0,
"m/s": 3.6,
"mph": 1.609344,
"knot": 1.852,
}

speed_chart_inverse: dict[str, float] = {
"km/h": 1.0,
"m/s": 0.277777778,
"mph": 0.621371192,
"knot": 0.539956803,
}

def convert_speed(speed: float, unit_from: str, unit_to: str) -> float:
"""
Convert speed from one unit to another using the speed_chart above.

"km/h": 1.0,
"m/s": 3.6,
"mph": 1.609344,
"knot": 1.852,

>>> convert_speed(100, "km/h", "m/s")
27.778
>>> convert_speed(100, "km/h", "mph")
62.137
>>> convert_speed(100, "km/h", "knot")
53.996
>>> convert_speed(100, "m/s", "km/h")
360.0
>>> convert_speed(100, "m/s", "mph")
223.694
>>> convert_speed(100, "m/s", "knot")
194.384
>>> convert_speed(100, "mph", "km/h")
160.934
>>> convert_speed(100, "mph", "m/s")
44.704
>>> convert_speed(100, "mph", "knot")
86.898
>>> convert_speed(100, "knot", "km/h")
185.2
>>> convert_speed(100, "knot", "m/s")
51.444
>>> convert_speed(100, "knot", "mph")
115.078
"""
if unit_to not in speed_chart or unit_from not in speed_chart_inverse:
raise ValueError(
f"Incorrect 'from_type' or 'to_type' value: {unit_from!r}, {unit_to!r}\n"
f"Valid values are: {', '.join(speed_chart_inverse)}"
)
return round(speed * speed_chart[unit_from] * speed_chart_inverse[unit_to], 3)

if __name__ == "__main__":
import doctest

doctest.testmod()
```