def add_extra_container(self, container, error_on_exists=False):
if container in self.extra_containers:<EOL><INDENT>if error_on_exists:<EOL><INDENT>raise DatacatsError('<STR_LIT>'.format(container))<EOL><DEDENT>else:<EOL><INDENT>return<EOL><DEDENT><DEDENT>self.extra_containers.append(container)<EOL>cp = SafeConfigParser()<EOL>cp.read(self.target + '<STR_LIT>')<EOL>cp.set('<STR_LIT>', '<STR_LIT>', '<STR_LIT:U+0020>'.join(self.extra_containers))<EOL>with open(self.target + '<STR_LIT>', '<STR_LIT:w>') as f:<EOL><INDENT>cp.write(f)<EOL><DEDENT>
Add a container as a 'extra'. These are running containers which are not necessary for
running default CKAN but are useful for certain extensions
:param container: The container name to add
:param error_on_exists: Raise a DatacatsError if the extra container already exists.