def to_true(amount: float, flag: str, mag_var: float) -> float:
    """
    Returns True bearing or Course
    :param amount: value of direction in degrees
    :param flag: T = True M = Magnetic
    :param mag_var:  variation to correct magnetic values
    :return: True value
    """
    value = amount
    if flag == 'M':
        value = amount - mag_var
    return value