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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 set_install_id(filename, install_id):
 """ Set install id for library named in `filename` Parameters filename : str filename of library install_id : str install id for library `filename` Raises ------ RuntimeError if `filename` has not install id """

    if get_install_id(filename) is None:
        raise InstallNameError('{0} has no install id'.format(filename))
    back_tick(['install_name_tool', '-id', install_id, filename])