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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 move_enrollment(session, enrollment, uidentity):
 """Move an enrollment to a unique identity. Shifts `enrollment` to the unique identity given in `uidentity`. The function returns whether the operation was executed successfully. When `uidentity` is the unique identity currently related to `enrollment`, this operation does not have any effect and `False` will be returned as result. :param session: database session :param enrollment: enrollment to be moved :param uidentity: unique identity where `enrollment` will be moved :return: `True` if the enrollment was moved; `False` in any other case """

    if enrollment.uuid == uidentity.uuid:
        return False

    old_uidentity = enrollment.uidentity
    enrollment.uidentity = uidentity

    last_modified = datetime.datetime.utcnow()

    old_uidentity.last_modified = last_modified
    uidentity.last_modified = last_modified

    session.add(uidentity)
    session.add(old_uidentity)

    return True