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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 describe(self):
 """Describe all serialized fields. It returns dictionary of all fields description defined for this serializer using their own ``describe()`` methods with respect to order in which they are defined as class attributes. Returns: OrderedDict: serializer description """

        return OrderedDict([
            (name, field.describe())
            for name, field in self.fields.items()
        ])