set_app_options

How to set the app_options in ICC2 to default values.
For ex:
set_app_options -name plan.macro.buffer_channel_height -value 10um
set_app_options -name plan.macro.buffer_channel_width -value 10um
set_app_options -name plan.macro.spacing_rule_widths -value { 5um 5um }
set_app_options -name plan.macro.spacing_rule_heights -value { 5um 5um }
How to set back to system default values in single command.
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Pruthvi