human
Solve the following python programming problem given the following code:
def _generate_dispatch(cls) : 
    'Return an optimized visit dispatch function for the cls
    for use by the compiler.
    ' 
    if ('__visit_name__' in cls.__dict__) : 
        visit_name = cls.__visit_name__ 
        if isinstance (getter, str) : 
            getter = operator.attrgetter (('visit_%s' % visit_name)) 
            def _compiler_dispatch(self, visitor, **kw) : 
                try : 
                    meth = getter (visitor) 
except AttributeError : 
                    raise exc.UnsupportedCompilationError (visitor, cls) 
else : 
                    return meth (self, ** kw) 
else : 
            def _compiler_dispatch(self, visitor, **kw) : 
                visit_attr = ('visit_%s' % self.__visit_name__) 
                try : 
                    meth = getattr (visitor, visit_attr) 
except AttributeError : 
                    raise exc.UnsupportedCompilationError (visitor, cls) 
else : 
                    return meth (self, ** kw) 
_compiler_dispatch.__doc__ = 'Look for an attribute named "visit_" + self.__visit_name__
            on the visitor, and call it with the same kw params.
            ' 
        cls._compiler_dispatch = _compiler_dispatch 

    
    

    Fix the buggy line: if isinstance (getter, str) :
assistant
#Here is Python program to fix the buggy line: if isinstance (getter, str) :
.

if isinstance (visit_name, str) :