Constant passing in Hamilton

indicators.py

import pandas as pd

def total_distance_travelled_by_train( ... ) -> pd.Series:
    return # placeholder -- fill with actual logic, etc.
    
def distance_travelled_till_intermediate_station( ... ) -> pd.Series:
    return # placeholder -- fill with actual logic, etc.


def journey_distance(total_distance_travelled_by_train: pd.Series, distance_travelled_till_intermediate_station: pd.Series) -> pd.Series:
    return total_distance_travelled_by_train - distance_travelled_till_intermediate_station


def normalized_journey_distance(journey_distance: pd.Series, average_distance_travelled: float) -> pd.Series:
    return journey_distance / average_distance_travelled

run.py

from hamilton import driver
import indicators


# this constant can from somewhere else and be passed into the driver as "config", or as part of the execute() call (like I have below).
average_distance_travelled = 123.43


dr = driver.Driver({}, indicators)
df = dr.execute(['normalized_journey_distance'], inputs={
    'average_distance_travelled': average_distance_travelled
})
print(df)