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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 create_missing(self):
 """Automatically populate additional instance attributes. When a new lifecycle environment is created, it must either: * Reference a parent lifecycle environment in the tree of lifecycle environments via the ``prior`` field, or * have a name of "Library". Within a given organization, there can only be a single lifecycle environment with a name of 'Library'. This lifecycle environment is at the root of a tree of lifecycle environments, so its ``prior`` field is blank. This method finds the 'Library' lifecycle environment within the current organization and points to it via the ``prior`` field. This is not done if the current lifecycle environment has a name of 'Library'. """

        # We call `super` first b/c it populates `self.organization`, and we
        # need that field to perform a search a little later.
        super(LifecycleEnvironment, self).create_missing()
        if (self.name != 'Library' and  # pylint:disable=no-member
                not hasattr(self, 'prior')):
            results = self.search({'organization'}, {u'name': u'Library'})
            if len(results) != 1:
                raise APIResponseError(
                    u'Could not find the "Library" lifecycle environment for '
                    u'organization {0}. Search results: {1}'
                    .format(self.organization, results)  # pylint:disable=E1101
                )
            self.prior = results[0]