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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 ensure_built(self, headers=None):
 """ Make sure that a dictionary exists for this type. """

        if not self.params:
            return
        else:
            for child in self.params:
                child.ensure_built(headers=headers)
        if headers is None:
            headers = self.guess_headers
        generate(str(self), headers,
                 has_iterators=self.name in HAS_ITERATORS)