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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 transform_point(point, source_crs, target_crs):
 """ Maps point form src_crs to tgt_crs :param point: a tuple `(x, y)` :type point: (float, float) :param source_crs: source CRS :type source_crs: constants.CRS :param target_crs: target CRS :type target_crs: constants.CRS :return: point in target CRS :rtype: (float, float) """

    if source_crs == target_crs:
        return point
    old_x, old_y = point
    new_x, new_y = pyproj.transform(CRS.projection(source_crs), CRS.projection(target_crs), old_x, old_y)
    return new_x, new_y