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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_name(filename, oldname, newname):
 """ Set install name `oldname` to `newname` in library filename Parameters filename : str filename of library oldname : str current install name in library newname : str replacement name for `oldname` """

    names = get_install_names(filename)
    if oldname not in names:
        raise InstallNameError('{0} not in install names for {1}'.format(
            oldname, filename))
    back_tick(['install_name_tool', '-change', oldname, newname, filename])