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Changes between Initial Version and Version 1 of Ticket #29562

initial	v1
5	5	My idea is to allow provide a callback function to tell the cache how to get the data. and only call the function when cache expires.
6	6
	7	Although custom tags can be used to get the data in the cache, custom tags don't seem to handle html code very well.
	8
7	9	I have tried it many times and found out how to make the simplest changes to complete this feature and ensure its compatibility.
8	10