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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _build_compatibility_members(binding, decorators=None):
 """Apply `binding` to QtCompat Arguments: binding (str):
 Top level binding in _compatibility_members. decorators (dict, optional):
 Provides the ability to decorate the original Qt methods when needed by a binding. This can be used to change the returned value to a standard value. The key should be the classname, the value is a dict where the keys are the target method names, and the values are the decorator functions. """


    decorators = decorators or dict()

    # Allow optional site-level customization of the compatibility members.
    # This method does not need to be implemented in QtSiteConfig.
    try:
        import QtSiteConfig
    except ImportError:
        pass
    else:
        if hasattr(QtSiteConfig, 'update_compatibility_decorators'):
            QtSiteConfig.update_compatibility_decorators(binding, decorators)

    _QtCompat = type("QtCompat", (object,), {})

    for classname, bindings in _compatibility_members[binding].items():
        attrs = {}
        for target, binding in bindings.items():
            namespaces = binding.split('.')
            try:
                src_object = getattr(Qt, "_" + namespaces[0])
            except AttributeError as e:
                _log("QtCompat: AttributeError: %s" % e)
                # Skip reassignment of non-existing members.
                # This can happen if a request was made to
                # rename a member that didn't exist, for example
                # if QtWidgets isn't available on the target platform.
                continue

            # Walk down any remaining namespace getting the object assuming
            # that if the first namespace exists the rest will exist.
            for namespace in namespaces[1:]:
                src_object = getattr(src_object, namespace)

            # decorate the Qt method if a decorator was provided.
            if target in decorators.get(classname, []):
                # staticmethod must be called on the decorated method to
                # prevent a TypeError being raised when the decorated method
                # is called.
                src_object = staticmethod(
                    decorators[classname][target](src_object))

            attrs[target] = src_object

        # Create the QtCompat class and install it into the namespace
        compat_class = type(classname, (_QtCompat,), attrs)
        setattr(Qt.QtCompat, classname, compat_class)