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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 to_versions(self):
 """Returns exact version ranges as Version objects, or None if there are no exact version ranges present. """

        versions = []
        for bound in self.bounds:
            if bound.lower.inclusive and bound.upper.inclusive \
                    and (bound.lower.version == bound.upper.version):
                versions.append(bound.lower.version)

        return versions or None