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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def distance_to_angle(distance, units='metric'):
 """Convert a distance in to an angle along a great circle. Args: distance (float):
 Distance to convert to degrees units (str):
 Unit type to be used for distances Returns: float: Angle in degrees Raises: ValueError: Unknown value for ``units`` """

    if units in ('km', 'metric'):
        pass
    elif units in ('sm', 'imperial', 'US customary'):
        distance *= STATUTE_MILE
    elif units in ('nm', 'nautical'):
        distance *= NAUTICAL_MILE
    else:
        raise ValueError('Unknown units type %r' % units)

    return math.degrees(distance / BODY_RADIUS)