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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 register_admin(app, admin):
 """Called on app initialization to register administration interface."""

    category = 'Knowledge'
    admin.category_icon_classes[category] = "fa fa-mortar-board"
    admin.add_view(
        KnowledgeAdmin(app, KnwKB, db.session,
                       name='Knowledge Base', category=category,
                       endpoint="kb")
    )
    admin.add_view(
        KnwKBRVALAdmin(app, KnwKBRVAL, db.session,
                       name="Knowledge Mappings", category=category,
                       endpoint="kbrval")
    )