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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 find_mean_vector(*args, **kwargs):
 """ Returns the mean vector for a set of measurments. By default, this expects the input to be plunges and bearings, but the type of input can be controlled through the ``measurement`` kwarg. Parameters *args : 2 or 3 sequences of measurements By default, this will be expected to be ``plunge`` & ``bearing``, both array-like sequences representing linear features. (Rake measurements require three parameters, thus the variable number of arguments.) The *measurement* kwarg controls how these arguments are interpreted. measurement : string, optional Controls how the input arguments are interpreted. Defaults to ``"lines"``. May be one of the following: ``"poles"`` : strikes, dips Arguments are assumed to be sequences of strikes and dips of planes. Poles to these planes are used for analysis. ``"lines"`` : plunges, bearings Arguments are assumed to be sequences of plunges and bearings of linear features. ``"rakes"`` : strikes, dips, rakes Arguments are assumed to be sequences of strikes, dips, and rakes along the plane. ``"radians"`` : lon, lat Arguments are assumed to be "raw" longitudes and latitudes in the stereonet's underlying coordinate system. Returns ------- mean_vector : tuple of two floats The plunge and bearing of the mean vector (in degrees). r_value : float The length of the mean vector (a value between 0 and 1). """

    lon, lat = _convert_measurements(args, kwargs.get('measurement', 'lines'))
    vector, r_value = stereonet_math.mean_vector(lon, lat)
    plunge, bearing = stereonet_math.geographic2plunge_bearing(*vector)
    return (plunge[0], bearing[0]), r_value