Stop caching propnames?

[michael-k]

I've noticed in troposphere that with self.propnames = props.keys() the object can no longer be pickled.

• Does AWSObject need to be able to be pickled?

• Is it even necessary to cache the keys? name in self.props (.keys() is not necessary) should be just as fast as name in self.propnames.

I don't see a reason for caching here.

See b4e4008#diff-7026bda438cf5fffa3496ee838ea9504d1962b37c3e1c573f34b09ebe4b4588cL21-R21

[zdot]

Our code uses deepcopy to create copies of Troposphere templates (including any awacs statements) that can be safely mutated for various purposes. Removing list() breaks this functionality for us (because of the pickling issue). Is it possible to restore the list call, or else get rid of the cache altogether as @michael-k suggests above?