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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 add_to_linestring(position_data, kml_linestring):
    '''add a point to the kml file'''
    global kml

    # add altitude offset
    position_data[2] += float(args.aoff)
    kml_linestring.coords.addcoordinates([position_data])