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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 writeSequence(self, iterable):
 """ Encodes an iterable. The default is to write If the iterable has an al """

        try:
            alias = self.context.getClassAlias(iterable.__class__)
        except (AttributeError, pyamf.UnknownClassAlias):
            self.writeList(iterable)

            return

        if alias.external:
            # a is a subclassed list with a registered alias - push to the
            # correct method
            self.writeObject(iterable)

            return

        self.writeList(iterable)