user: You are a structured reasoning expert tasked with solving problems step by step. 
You first think about the reasoning process in the mind and then provide the answer. The reasoning process and answer should be enclosed within <think> </think> and <answer> </answer> tags, respectively, i.e., <think> reasoning process here </think> <answer> answer here </answer>. 
Given a question and the associated knowledge graph triplets (entity, relation, entity), you are asked to answer the question with these triplets and your own knowledge. 
You can break down the original question into several sub-questions and explore the given knowledge graph to solve them step-by-step. If there are multiple possible answers, choose one as the final answer. 
After thinking, when you finally reach a conclusion, clearly state the answer within <answer> </answer> tags, i.e., <answer> answer here </answer>. 
Question: what locomotive builder built the south african class 5e, series 3? 
Knowledge Triplets: South African Class 5E, Series 3, rail.locomotive_class.built_by, English Electric
British Rail Class 40, rail.locomotive_class.built_by, English Electric
English Electric, aviation.aircraft_manufacturer.aircraft_models_made, English Electric Lightning
English Electric, rail.locomotive_builder.locomotive_classes_built, g.120lwxdk
English Electric, rail.locomotive_builder.locomotive_classes_built, British Rail Class 08
NZR EO class, rail.locomotive_class.built_by, English Electric
English Electric, rail.locomotive_builder.locomotive_classes_built, New Zealand DM class electric multiple unit
BHP Port Kembla D16 class, rail.locomotive_class.built_by, English Electric
m.04xdcpl, organization.organization_merger.organizations_merging, English Electric
English Electric, rail.locomotive_builder.locomotive_classes_built, WAGR K class
BHP Port Kembla D35 class, rail.locomotive_class.built_by, English Electric
English Electric, rail.locomotive_builder.locomotive_classes_built, New Zealand DE class locomotive
English Electric, rail.locomotive_builder.locomotive_classes_built, British Rail Class 12
English Electric, rail.locomotive_builder.locomotive_classes_built, South Australian Railways 800 class
English Electric, rail.locomotive_builder.locomotive_classes_built, British Rail Class 13
English Electric, rail.locomotive_builder.locomotive_classes_built, British Rail Class 09
g.120lwxdk, rail.locomotive_class.built_by, English Electric
English Electric, rail.locomotive_builder.locomotive_classes_built, Queensland Railways 1250 class
English Electric, rail.locomotive_builder.locomotive_classes_built, BHP Port Kembla D9 class
Rhodesia Railways class DE2, rail.locomotive_class.built_by, English Electric
WAGR R class, rail.locomotive_class.built_by, English Electric
MRWA F class, rail.locomotive_class.built_by, English Electric
English Electric, rail.locomotive_builder.locomotive_classes_built, BHP Port Kembla D35 class
English Electric Canberra, aviation.aircraft_model.manufacturer, English Electric
English Electric, rail.locomotive_builder.locomotive_classes_built, South African Class 5E, Series 2
Victorian Railways F class, rail.locomotive_class.built_by, English Electric
English Electric, rail.locomotive_builder.locomotive_classes_built, MRWA G class
English Electric, rail.locomotive_builder.locomotive_classes_built, BHP Port Kembla D16 class
English Electric, rail.locomotive_builder.locomotive_classes_built, BHP Port Kembla D1 class
WAGR K class, rail.locomotive_class.built_by, English Electric
New Zealand E class locomotive, rail.locomotive_class.built_by, English Electric
English Electric, organization.organization.child, m.04kjz00
English Electric, rail.locomotive_builder.locomotive_classes_built, English Electric diesel engines
English Electric Kingston, aviation.aircraft_model.manufacturer, English Electric
English Electric, rail.locomotive_builder.locomotive_classes_built, South Australian Railways 500 class
English Electric, rail.locomotive_builder.locomotive_classes_built, NZR EO class
English Electric, rail.locomotive_builder.locomotive_classes_built, British Rail GT3
de Havilland Vampire, aviation.aircraft_model.manufacturer, English Electric
English Electric, rail.locomotive_builder.locomotive_classes_built, Queensland Railways 2370 class
South African Class 5E, Series 2, rail.locomotive_class.built_by, English Electric
Felixstowe F.3, aviation.aircraft_model.manufacturer, English Electric
English Electric, rail.locomotive_builder.locomotive_classes_built, New Zealand E class locomotive
South African Class 5E, Series 3, rail.locomotive_class.length, 15.494
English Electric, rail.locomotive_builder.locomotive_classes_built, British Rail Class 20
English Electric, rail.locomotive_builder.locomotive_classes_built, PKP class EU06
PKP class EU06, rail.locomotive_class.built_by, English Electric
English Electric, rail.locomotive_builder.locomotive_classes_built, Queensland Railways 1620 class
British Rail Class 23, rail.locomotive_class.built_by, English Electric
English Electric, organization.organization.involved_in_merger, m.04xdcpl
NZR DI class, rail.locomotive_class.built_by, English Electric
NZR DG class, rail.locomotive_class.built_by, English Electric
English Electric diesel engines, rail.locomotive_class.built_by, English Electric
Queensland Railways 2350 class, rail.locomotive_class.built_by, English Electric
English Electric, rail.locomotive_builder.locomotive_classes_built, British Rail Class 73
g.1213jfb6, rail.locomotive_class.built_by, English Electric
English Electric, rail.locomotive_builder.locomotive_classes_built, Queensland Railways 1270 class
English Electric, rail.locomotive_builder.locomotive_classes_built, g.1213jfb6
British Rail Class 20, rail.locomotive_class.built_by, English Electric
English Electric, rail.locomotive_builder.locomotive_classes_built, British Railways D0226
British Rail Class D3/12, rail.locomotive_class.built_by, English Electric
New Zealand EW class locomotive, rail.locomotive_class.built_by, English Electric
English Electric, rail.locomotive_builder.locomotive_classes_built, CP Class 1400
British Rail Class 86, rail.locomotive_class.built_by, English Electric
English Electric, organization.organization.headquarters, m.0y5fg11
English Electric, rail.locomotive_builder.locomotive_classes_built, British Rail Class 86
Queensland Railways 1270 class, rail.locomotive_class.built_by, English Electric
South Australian Railways 500 class, rail.locomotive_class.built_by, English Electric
British Rail Class 83, rail.locomotive_class.built_by, English Electric
British Rail Class 50, rail.locomotive_class.built_by, English Electric
English Electric, rail.locomotive_builder.locomotive_classes_built, WAGR C class
English Electric, rail.locomotive_builder.locomotive_classes_built, NZR EC class
English Electric, rail.locomotive_builder.locomotive_classes_built, Tasmanian Government Railways Za class
British Rail Class 37, rail.locomotive_class.built_by, English Electric
English Electric, aviation.aircraft_manufacturer.aircraft_models_made, Felixstowe F.3
MRWA G class, rail.locomotive_class.built_by, English Electric
WAGR C class, rail.locomotive_class.built_by, English Electric
English Electric Lightning, aviation.aircraft_model.manufacturer, English Electric
Tasmanian Government Railways Z class, rail.locomotive_class.built_by, English Electric
English Electric, rail.locomotive_builder.locomotive_classes_built, WAGR H class
English Electric, rail.locomotive_builder.locomotive_classes_built, South African Class 5E, Series 1
English Electric, rail.locomotive_builder.locomotive_classes_built, British Rail Class D3/11
m.04zs3m5, business.employment_tenure.company, English Electric
Queensland Railways 2370 class, rail.locomotive_class.built_by, English Electric
British Rail Class 09, rail.locomotive_class.built_by, English Electric
British Rail Class 13, rail.locomotive_class.built_by, English Electric
Felixstowe F.5, aviation.aircraft_model.manufacturer, English Electric
English Electric, rail.locomotive_builder.locomotive_classes_built, NZR DF class
English Electric, rail.locomotive_builder.locomotive_classes_built, Victorian Railways F class
Queensland Railways 1300 class, rail.locomotive_class.built_by, English Electric
Queensland Railways 1200 class, rail.locomotive_class.built_by, English Electric
English Electric, rail.locomotive_builder.locomotive_classes_built, Tasmanian Government Railways X class
English Electric, rail.locomotive_builder.locomotive_classes_built, BHP Port Kembla D34 class
South African Class 5E, Series 3, rail.locomotive_class.uic_classification, Bo-Bo
English Electric, rail.locomotive_builder.locomotive_classes_built, British Rail Class 23
English Electric, rail.locomotive_builder.locomotive_classes_built, NZR DG class
English Electric, rail.locomotive_builder.locomotive_classes_built, NS Class 600
British Rail Class D3/6, rail.locomotive_class.built_by, English Electric
British Rail Class 73, rail.locomotive_class.built_by, English Electric
English Electric, rail.locomotive_builder.locomotive_classes_built, Tasmanian Government Railways Z class
English Electric, rail.locomotive_builder.locomotive_classes_built, British Rail Class 50
English Electric, aviation.aircraft_manufacturer.aircraft_models_made, English Electric Wren
English Electric, rail.locomotive_builder.locomotive_classes_built, NZR DI class
Tasmanian Government Railways Za class, rail.locomotive_class.built_by, English Electric
New Zealand DE class locomotive, rail.locomotive_class.built_by, English Electric
British Rail DP2, rail.locomotive_class.built_by, English Electric
English Electric, rail.locomotive_builder.locomotive_classes_built, British Rail Class 40
CP Class 1400, rail.locomotive_class.built_by, English Electric
English Electric Ayr, aviation.aircraft_model.manufacturer, English Electric
WAGR H class, rail.locomotive_class.built_by, English Electric
NIR 1 Class, rail.locomotive_class.built_by, English Electric
Victorian Railways L class, rail.locomotive_class.built_by, English Electric
English Electric, rail.locomotive_builder.locomotive_classes_built, WAGR R class
English Electric, aviation.aircraft_manufacturer.aircraft_models_made, Felixstowe F.5
English Electric, aviation.aircraft_manufacturer.aircraft_models_made, English Electric Kingston
English Electric, rail.locomotive_builder.locomotive_classes_built, NZR ED class
British Rail GT3, rail.locomotive_class.built_by, English Electric
English Electric, rail.locomotive_builder.locomotive_classes_built, New Zealand EW class locomotive
English Electric Wren, aviation.aircraft_model.manufacturer, English Electric
New Zealand DM class electric multiple unit, rail.locomotive_class.built_by, English Electric
British Rail Class 08, rail.locomotive_class.built_by, English Electric
NZR EC class, rail.locomotive_class.built_by, English Electric
British Rail Class 12, rail.locomotive_class.built_by, English Electric
English Electric, business.employer.employees, m.04zs3m5
English Electric, rail.locomotive_builder.locomotive_classes_built, British Rail Class 55
English Electric, aviation.aircraft_manufacturer.aircraft_models_made, English Electric Canberra
Queensland Railways 1600 class, rail.locomotive_class.built_by, English Electric
English Electric, rail.locomotive_builder.locomotive_classes_built, British Rail Class 11
BHP Port Kembla D1 class, rail.locomotive_class.built_by, English Electric
British Rail Class 11, rail.locomotive_class.built_by, English Electric
BHP Port Kembla D9 class, rail.locomotive_class.built_by, English Electric
English Electric, rail.locomotive_builder.locomotive_classes_built, Tasmanian Government Railways Y class
South African Class 5E, Series 1, rail.locomotive_class.built_by, English Electric
CP Class 1800, rail.locomotive_class.built_by, English Electric
British Rail Class D3/11, rail.locomotive_class.built_by, English Electric
NZR ED class, rail.locomotive_class.built_by, English Electric
English Electric, user.avh.default_domain.ellerdale_topic.ellerdale_id, 0081-ac53
English Electric, rail.locomotive_builder.locomotive_classes_built, British Rail Class 37
English Electric, rail.locomotive_builder.locomotive_classes_built, Victorian Railways L class
English Electric, rail.locomotive_builder.locomotive_classes_built, English Electric EL.100
English Electric, business.defunct_company.ceased_operations, 1968
British Railways D0226, rail.locomotive_class.built_by, English Electric
English Electric, organization.organization.date_founded, 1918
English Electric, rail.locomotive_builder.locomotive_classes_built, Queensland Railways 1200 class
South Australian Railways 800 class, rail.locomotive_class.built_by, English Electric
English Electric, rail.locomotive_builder.locomotive_classes_built, Queensland Railways 1600 class
m.04kjz00, organization.organization_relationship.parent, English Electric
Tasmanian Government Railways Y class, rail.locomotive_class.built_by, English Electric
English Electric, rail.locomotive_builder.locomotive_classes_built, South African Class 5E, Series 3
English Electric, rail.locomotive_builder.locomotive_classes_built, Queensland Railways 1300 class
English Electric, rail.locomotive_builder.locomotive_classes_built, British Rail Class D3/10
English Electric, rail.locomotive_builder.locomotive_classes_built, British Rail DP2
English Electric, aviation.aircraft_manufacturer.aircraft_models_made, de Havilland Vampire
English Electric, rail.locomotive_builder.locomotive_classes_built, CP Class 1800
English Electric, organization.organization.headquarters, m.0h7tlwl
m.04kjz06, organization.organization_relationship.parent, English Electric
BHP Port Kembla D34 class, rail.locomotive_class.built_by, English Electric
English Electric, rail.locomotive_builder.locomotive_classes_built, Queensland Railways 2350 class
English Electric, rail.locomotive_builder.locomotive_classes_built, British Rail Class D3/6
British Rail Class D3/10, rail.locomotive_class.built_by, English Electric
NZR DF class, rail.locomotive_class.built_by, English Electric
English Electric, organization.organization.child, m.04kjz06
Tasmanian Government Railways X class, rail.locomotive_class.built_by, English Electric
British Rail Class 55, rail.locomotive_class.built_by, English Electric
Queensland Railways 1620 class, rail.locomotive_class.built_by, English Electric
English Electric, aviation.aircraft_manufacturer.aircraft_models_made, English Electric Ayr
English Electric EL.100, rail.locomotive_class.built_by, English Electric
English Electric, rail.locomotive_builder.locomotive_classes_built, MRWA F class
English Electric, rail.locomotive_builder.locomotive_classes_built, Rhodesia Railways class DE2
English Electric, rail.locomotive_builder.locomotive_classes_built, British Rail Class 83
English Electric, rail.locomotive_builder.locomotive_classes_built, NIR 1 Class
English Electric, rail.locomotive_builder.locomotive_classes_built, British Rail Class D3/12
Queensland Railways 1250 class, rail.locomotive_class.built_by, English Electric
NS Class 600, rail.locomotive_class.built_by, English Electric

Answer: English Electric