import math


def convert_meters_to_degrees(radius_m, rnd_dir='closest', places=7):
    """
    Takes a measurement in meters and, optionally, a direction in which to
    round the conversion and the number of decimal places for the result.
    Returns the degrees latitude at the Equator. Because the conversion is based
    on the circumference of the Earth at the Equator, conersions at other
    latitudes will not be accurate.
    """
    raw_degrees = radius_m / 111319.444

    conversion = {
        'closest': round(raw_degrees, places),
        'down': (math.floor(raw_degrees * 10**places)) / 10**places,
        'up': (math.ceil(raw_degrees * 10**places)) / 10**places
    }

    return conversion[rnd_dir]