[Python] Is it possible to make a pointer with forced parameter values?

Consider this ServicesManager class that handles some services (basically, a function identified by a name):

class ServicesManager:
def __init__(self):
self.services = dict()

def add_service(self,name,func):
self.services[name] = func

def call_service(self,name):
self.services[name](name)


This is a MCVE, to help asking my question. ServicesManager is actually a ROS Node class. It cannot be modified to find an answer to my question.

Here is a class using ServicesManager with an example of usage:

class B(ServicesManager):
def __init__(self):
super(B, self).__init__()
self.add_service("foo",self.service_foo)
self.add_service("bar",self.service_bar)

def service_foo(self,name):
# do something
print(name)

def service_bar(self,name):
# do something
print(name)

b = B()
b.call_service("foo")
b.call_service("bar")


The service_foo and service_bar # do something part has very common piece of code that I would like to factorize, I'd like an object to be passed to a generic function. The code would look like this:

class B(ServicesManager):

class helper_object_foo():
def func1(self,name):
pass
def func2(self):
pass

class helper_object_bar():
def func1(self,name):
pass
def func2(self):
pass

def __init__(self):
super(B, self).__init__()
#self.add_service("foo",self.service_foo)
#self.add_service("bar",self.service_bar)
# How to call add_service???
self.add_service("foo",?? self.service_generic_func using helper_object_foo())
self.add_service("bar",?? self.service_generic_func using helper_object_bar())

def service_generic_func(self,name,helper_object):
helper_object.func1(name)
helper_object.func2()
print(name)


Is there a way to do this? What would be the good syntax for calling add_service? May a lambda help?

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