def __call__(self, element, compiler, **kw):
        # TODO: yes, this could also switch off of DBAPI in use.
        fn = self.specs.get(compiler.dialect.name, None)
        if not fn:
            try:
                fn = self.specs['default']
            except __HOLE__:
                raise exc.CompileError(
                    "%s construct has no default "
                    "compilation handler." % type(element))
        return fn(element, compiler, **kw)
dataset/ETHPy150Open zzzeek/sqlalchemy/lib/sqlalchemy/ext/compiler.py/_dispatcher.__call__