def geometry_linestring(lat, lon, elev):
    """
    GeoJSON Linestring. Latitude and Longitude have 2 values each.
    :param list lat: Latitude values
    :param list lon:  Longitude values
    :return dict:
    """
    logger_excel.info("enter geometry_linestring")
    d = OrderedDict()
    coordinates = []
    temp = ["", ""]

    # Point type, Matching pairs.
    if lat[0] == lat[1] and lon[0] == lon[1]:
        logger_excel.info("matching geo coordinate")
        lat.pop()
        lon.pop()
        d = geometry_point(lat, lon, elev)

    else:
        # Creates coordinates list
        logger_excel.info("unique geo coordinates")
        for i in lon:
            temp[0] = i
            for j in lat:
                temp[1] = j
                coordinates.append(copy.copy(temp))
        if elev:
            for i in coordinates:
                i.append(elev)
        # Create geometry block
        d['type'] = 'Linestring'
        d['coordinates'] = coordinates
    logger_excel.info("exit geometry_linestring")
    return d