id	summary	reporter	owner	description	type	status	component	version	severity	resolution	keywords	cc	stage	has_patch	needs_docs	needs_tests	needs_better_patch	easy	ui_ux
17634	MultiValueDict.appendlist is ineffective	Miloslav Pojman	nobody	"Current MultiValueDict.appendlist implementation uses + operator in order to merge two lists -- which is pretty ineffective.

When I replaced a list merge by a simple append call I got aprox. 20% execution time of the original implementation:

{{{
    def appendlist(self, key, value):
        super(MultiValueDict, self).setdefault(key, []).append(value)
}}}

Many calls to appendlist method are possible if the MultiValueDict is being built incrementally (for example when reading response from a remote API).

"	Cleanup/optimization	closed	Core (Other)	1.3	Normal	fixed		miloslav.pojman@… charette.s@…	Ready for checkin	1	0	0	0	1	0