Question: When was the British former professional boxer born who competed from 1971 to 1980 who had a bout with Jorge Victor Ahumada?
Sentence (from "John Conteh"): John Anthony Conteh, {'1': ", '2': ", '3': ", '4': "} (born 27 May 1951) is a British former professional boxer who competed from 1971 to 1980.
Relevant evidence: Yes