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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 find_unique_identity(session, uuid):
 """Find a unique identity. Find a unique identity by its UUID using the given `session`. When the unique identity does not exist the function will return `None`. :param session: database session :param uuid: id of the unique identity to find :returns: a unique identity object; `None` when the unique identity does not exist """

    uidentity = session.query(UniqueIdentity). \
        filter(UniqueIdentity.uuid == uuid).first()

    return uidentity