Crash when viewing file info dialog

Traceback (most recent call last):
File "./picard/ui/coverartbox.py", line 287, in show_cover_art_info
self.parent.view_info(default_tab=1)
File "./picard/ui/mainwindow.py", line 849, in view_info
dialog = TrackInfoDialog(track, self)
File "./picard/ui/infodialog.py", line 317, in _init_
InfoDialog._init_(self, track, parent)
File "./picard/ui/infodialog.py", line 142, in _init_
self._display_tabs()
File "./picard/ui/infodialog.py", line 145, in _display_tabs
self._display_info_tab()
File "./picard/ui/infodialog.py", line 333, in _display_info_tab
info_files = [FileInfoDialog.format_file_info(file) for file in track.linked_files]
File "./picard/ui/infodialog.py", line 280, in format_file_info
picard.util.htmlescape(i[1])), info))
File "./picard/ui/infodialog.py", line 279, in <lambda>
(picard.util.htmlescape(i[0]),
NameError: global name 'picard' is not defined