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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 add_organization(session, name):
 """Add an organization to the session. This function adds a new organization to the session, using the given `name` as an identifier. Name cannot be empty or `None`. It returns a new `Organization` object. :param session: database session :param name: name of the organization :return: a new organization :raises ValueError: when `name` is `None` or empty """

    if name is None:
        raise ValueError("'name' cannot be None")
    if name == '':
        raise ValueError("'name' cannot be an empty string")

    organization = Organization(name=name)

    session.add(organization)

    return organization