Question: who played young clark kent in 1978 superman
[{'answer': 'Jeff East', 'provenance': [{'wikipedia_id': '2003773', 'title': 'Jeff East', 'start_paragraph_id': 0, 'start_character': 0, 'end_paragraph_id': 0, 'end_character': 9, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '2003773', 'title': 'Jeff East', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 372, 'bleu_score': 0.8937168577929461, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 2987275424289698944}, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '362719', 'title': 'Superman (1978 film)', 'section': 'Section::::Production.:Development.:Casting of Superman.\n', 'start_paragraph_id': 47, 'end_paragraph_id': 47, 'meta': {'evidence_span': ["Jeff East portrays teenage Clark Kent. East's lines were overdubbed by Reeve during post-production", 'Jeff East portrays teenage Clark Kent.', "Jeff East portrays teenage Clark Kent. East's lines were overdubbed by Reeve during post-production."]}}]}, {'provenance': [{'wikipedia_id': '2003773', 'title': 'Jeff East', 'section': 'Section::::Abstract.', 'start_paragraph_id': 1, 'end_paragraph_id': 1, 'meta': {'evidence_span': ['Jeffrey Franklin East (born October 27, 1957) is an American actor. Beginning his professional acting career at the age of fourteen, East is known for his portrayal of Huckleberry Finn in the United Artists feature films "Tom Sawyer" (1973) and "Huckleberry Finn" (1974), as well as for his portrayal of a teenage Clark Kent in Richard Donner\'s "Superman:', 'as well as for his portrayal of a teenage Clark Kent in Richard Donner\'s "Superman: The Movie" (1978)', 'Jeffrey Franklin East (born October 27, 1957) is an American actor. Beginning his professional acting career at the age of fourteen, East is known for his portrayal of Huckleberry Finn in the United Artists feature films "Tom Sawyer" (1973) and "Huckleberry Finn" (1974), as well as for his portrayal of a teenage Clark Kent in Richard Donner\'s "Superman: The Movie" (1978). East was born in Kansas City, Missouri, to parents Ira and Joan Ann East.']}}]}, {'provenance': [{'wikipedia_id': '7442', 'title': 'Clark Kent', 'section': 'Section::::In other media.:Christopher Reeve "Superman" films (1978–1987) and "Superman Returns" (2006).\n', 'start_paragraph_id': 66, 'end_paragraph_id': 66, 'meta': {'evidence_span': ['In 1978, the first of four Superman films was made in which Clark Kent and Superman were portrayed by Christopher Reeve (with teenage Kent played by Jeff East in the first film).', '(with teenage Kent played by Jeff East in the first film).', 'In 1978, the first of four Superman films was made in which Clark Kent and Superman were portrayed by Christopher Reeve (with teenage Kent played by Jeff East in the first film).']}}]}]