def create(pathspec):
        """
        Create a new mailbox from the given hierarchical name.

        @type pathspec: L{bytes}
        @param pathspec: The full hierarchical name of a new mailbox to create.
            If any of the inferior hierarchical names to this one do not exist,
            they are created as well.

        @rtype: L{Deferred} or L{bool}
        @return: A true value if the creation succeeds, or a deferred whose
            callback will be invoked when the creation succeeds.

        @raise MailboxException: Raised if this mailbox cannot be added. This
            may also be raised asynchronously, if a L{Deferred} is returned.
        """

        Create a new mailbox from the given hierarchical name.

        @type pathspec: L{bytes}
        @param pathspec: The full hierarchical name of a new mailbox to create.
            If any of the inferior hierarchical names to this one do not exist,
            they are created as well.

        @rtype: L{Deferred} or L{bool}
        @return: A true value if the creation succeeds, or a deferred whose
            callback will be invoked when the creation succeeds.

        @raise MailboxException: Raised if this mailbox cannot be added. This
            may also be raised asynchronously, if a L{Deferred} is returned.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/mail/interfaces.py