human
Solve the following python programming problem given the following code:
def adapts(from_, to, extra = None, factory = None, cached = False, when = '') : 
    " A class advisor for declaring adapters.

    Parameters
    ----------
    from_ : type or interface
        What the adapter adapts *from*, or a list of such types or interfaces
        (the '_' suffix is used because 'from' is a Python keyword).
    to : type or interface
        What the adapter adapts *to*, or a list of such types or interfaces.
    factory : callable
        An (optional) factory for actually creating the adapters. This is
        any callable that takes a single argument which is the object to
        be adapted. The factory should return an adapter if it can
        perform the adaptation and **None** if it cannot.
    cached : bool
        Should the adapters be cached? If an adapter is cached, then the
        factory will produce at most one adapter per instance.
    when : str
        A Python expression that selects which instances of a particular type
        can be adapted by this factory. The expression is evaluated in a
        namespace that contains a single name *adaptee*, which is bound to the
        object to be adapted (e.g., 'adaptee.is_folder').

    Note
    ----
    The ``cached`` and ``when`` arguments are ignored if ``factory`` is
    specified.

    " 
    from traits.adaptation.api import register_factory 
    from traits.adaptation.cached_adapter_factory import CachedAdapterFactory 
    from traits.protocols.advice import addClassAdvisor 
    if (extra is not None) : 
        (adapter, from_, to) = (from_, to, extra) 
else : 
        adapter = None 
@ deprecated ("use the 'register_factory' function from 'traits.api' instead") 
    def callback(klass) : 
        ' Called when the class has been created. ' 
        if (type (from_) is not list) : 
            from_protocols = [from_] 
else : 
            from_protocols = from_ 
if (type (to) is not list) : 
            to_protocols = [to] 
else : 
            to_protocols = to 
if (factory is None) : 
           ...

    
    

    Fix the buggy line: addClassAdvisor (from_)
assistant
#Here is Python program to fix the buggy line: addClassAdvisor (from_)
.

addClassAdvisor (callback)