How to use the rope.refactor.functionutils.DefinitionInfo.read function in rope

def _get_passed_arguments_string(self):
        result = ''
        if self._is_host_used():
            result = 'self'
        definition_info = functionutils.DefinitionInfo.read(self.pyfunction)
        others = definition_info.arguments_to_string(1)
        if others:
            if result:
                result += ', '
            result += others
        return result

def _get_function_signature(self, pyfunction, add_module=False):
        location = self._location(pyfunction, add_module)
        if isinstance(pyfunction, pyobjects.PyFunction):
            info = functionutils.DefinitionInfo.read(pyfunction)
            return location + info.to_string()
        else:
            return '%s(%s)' % (location + pyfunction.get_name(),
                               ', '.join(pyfunction.get_param_names()))

def _get_definition_info(self):
        return rope.refactor.functionutils.DefinitionInfo.read(self.pyfunction)

def _get_definition_info(self):
        return rope.refactor.functionutils.DefinitionInfo.read(self.pyfunction)

def _definfo(self):
        return functionutils.DefinitionInfo.read(self.pyname.get_object())

def _get_function_signature(self, pyfunction, add_module=False):
        location = self._location(pyfunction, add_module)
        if isinstance(pyfunction, pyobjects.PyFunction):
            info = functionutils.DefinitionInfo.read(pyfunction)
            return location + info.to_string()
        else:
            return '%s(%s)' % (location + pyfunction.get_name(),
                               ', '.join(pyfunction.get_param_names()))

def _get_function_signature(self, pyfunction, add_module=False):
        location = self._location(pyfunction, add_module)
        if isinstance(pyfunction, pyobjects.PyFunction):
            info = functionutils.DefinitionInfo.read(pyfunction)
            return location + info.to_string()
        else:
            return '%s(%s)' % (location + pyfunction.get_name(),
                               ', '.join(pyfunction.get_param_names()))

def _get_function_signature(self, pyfunction, add_module=False):
        location = self._location(pyfunction, add_module)
        if isinstance(pyfunction, pyobjects.PyFunction):
            info = functionutils.DefinitionInfo.read(pyfunction)
            return location + info.to_string()
        else:
            return '%s(%s)' % (location + pyfunction.get_name(),
                               ', '.join(pyfunction.get_param_names()))