This scripts parses all vcards in the directory given with -d
and prints them in a format that is usable as $query-command in mutt.

The first non-option argument is interpreted as a pattern to filter the
resulting lines.

To use it instead of the aliases defined in your .muttrc, use:
set query_command="vcs_query.py -d ~/.maildir/zimbra/Contacts/cur/ %s"
bind    editor  "\t"       complete-query

As parsing can take some time, the results are cached in ~/.cache/vcs_query.