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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 contract_creation_exceptions():
 """Special migration for the blueprint to support Keystone V3. We drop all tenant_id columns and create project_id columns instead. """

    return {
        sa.Column: ['.'.join([table, 'project_id']) for table in get_tables()],
        sa.Index: get_tables()
    }