# Profile: Python basics
import math


def minutes_to_hours(minutes):
    """Convert a non-negative number of minutes into hours."""
    if minutes < 0:
        raise ValueError("minutes must be non-negative")
    return minutes / 60


def total_minutes(sessions):
    """Return the sum; an empty collection has total zero."""
    return sum(sessions)


print("Hours:", minutes_to_hours(90))
print("Total:", total_minutes([20, 30]))
print("Rounded up:", math.ceil(minutes_to_hours(95)))
# print displays a value; return hands a value back to the caller.