re trying to replace with.
        :param other: The provider we're trying to replace.
        :param problems: If False is returned, this will contain what
                         problems prevented replacement. This is currently
                         a tuple of the literal string 'cantreplace',
                         ``provider``, ``other``  and the set of requirements
                         that ``provider`` couldn't fulfill.
        :return: True if we can replace ``other`` with ``provider``, else
                 False.
        Ú