def __init__(<EOL>self,<EOL>ufos=None,<EOL>designspace=None,<EOL>glyphs_module=classes,<EOL>minimize_ufo_diffs=False,<EOL>):
self.glyphs_module = glyphs_module<EOL>self.minimize_ufo_diffs = minimize_ufo_diffs<EOL>if designspace is not None:<EOL><INDENT>if ufos:<EOL><INDENT>raise NotImplementedError<EOL><DEDENT>self.designspace = self._valid_designspace(designspace)<EOL><DEDENT>elif ufos:<EOL><INDENT>self.designspace = self._fake_designspace(ufos)<EOL><DEDENT>else:<EOL><INDENT>raise RuntimeError("<STR_LIT>")<EOL><DEDENT>self._font = None<EOL>"""<STR_LIT>"""<EOL>
Create a builder that goes from UFOs + designspace to Glyphs.

        If you provide:
            * Some UFOs, no designspace: the given UFOs will be combined.
                No instance data will be created, only the weight and width
                axes will be set up (if relevant).
            * A designspace, no UFOs: the UFOs will be loaded according to
                the designspace's sources. Instance and axis data will be
                converted to Glyphs.
            * Both a designspace and some UFOs: not supported for now.
                TODO: (jany) find out whether there is a use-case here?

        Keyword arguments:
        ufos -- The list of UFOs to combine into a GSFont
        designspace -- A MutatorMath Designspace to use for the GSFont
        glyphs_module -- The glyphsLib.classes module to use to build glyphsLib
                         classes (you can pass a custom module with the same
                         classes as the official glyphsLib.classes to get
                         instances of your own classes, or pass the Glyphs.app
                         module that holds the official classes to import UFOs
                         into Glyphs.app)
        minimize_ufo_diffs -- set to True to store extra info in .glyphs files
                              in order to get smaller diffs between UFOs
                              when going UFOs->glyphs->UFOs