def lerp(value1, value2, amt):
    """Calculates a number between two numbers at a specific increment. 
    The amt parameter is the amount to interpolate between the two values
    where 0.0 equal to the first point, 0.1 is very near the first point, 
    0.5 is half-way in between, etc"""
    return value1 + amt * (value2 - value1)