如何为Telegraf添加带有整数的全局标签?

I would like to add a global tag with integer value for Telegraf. The tag is as follows: kairos_opt.ttl = 1200

This sets the ttl for all data points using KairosDB as the underlying database.

When i add it as:

[global_tags]

kairos_opt.ttl = 1200

It throws an error as Error parsing /etc/telegraf/telegraf.conf, toml: line 5: parse error

Please point me in the direction of the solution.