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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 rc_notfound(cls, interface_type, resource_name=None):
 """Exception used when no resource class is provided and no default is found. """


        msg = "Resource class for %s not provided and default not found." % interface_type

        if resource_name:
            msg = "Could not parse '%s'. %s" % (resource_name, msg)

        return cls(msg)