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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_root_path(absolute_path, relative_path):
 """ Return the root path of a path relative to an absolute path. Example: @param absolute_path: an absolute path that is ended by the specified relative path. @param relative_path: a relative path that ends the specified absolute path. @return: the root path of the relative path. """

    _absolute_path = os.path.normpath(absolute_path)
    _relative_path = os.path.normpath(relative_path)

    index = _absolute_path.rfind(_relative_path)
    if index == -1 or len(_relative_path) + index < len(_absolute_path):
        raise ValueError('The relative path does not end the specified absolute path')

    return _absolute_path[:index]