Error managing features

[Gary Thomas <gary@mlbassoc.com>]

In my $DISTRO, I have a default set of image features:
   IMAGE_FEATURES ?= "package-management debug-tweaks "

I'd like to build a minimized image which leaves out the package stuff, so
I added this line to my <image>.bb:
   IMAGE_FEATURES := "${@oe_filter_out('package-management', '${IMAGE_FEATURES}', d)}"

Sadly, this gives me this error:
   ERROR: Failure expanding variable IMAGE_FEATURES[:=], expression was ${@oe_filter_out('package-management', 'package-management debug-tweaks  ${EXTRA_IMAGE_FEATURES}', d)} which 
triggered exception SyntaxError: EOL while scanning string literal (IMAGE_FEATURES[:=], line 1)

Any idea what I've done wrong?

Thanks

-- 
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Gary Thomas                 |  Consulting for the
MLB Associates              |    Embedded world
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