def set_image_comment(path,*args,**kwargs):
"""
takes any kwarg, to use as a labeled part of the comment.
can also take single arg to use as body of comment
"""
if args and not kwargs:
kwargs['body'] = '\n'.join(args)
image = Image(path)
image.readMetadata()
# append is a possible kwarg
append = True
existing = image.getComment() or "" if append else ""
comment_parts = [COMMENT_DELIMINATOR] if existing else []
for k,v in kwargs.iteritems():
if v is None:
continue
if k == 'append':
append = v
else:
template = TEMPLATES.get(k,"%s:%s" % (k,v))
comment_parts.append(template % v)
image.setComment(existing + "\n".join(comment_parts))
image.writeMetadata()
