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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 resolve_content_type(type_resolvers, request):
 # type: (Iterable[Callable[[Any], str]], Any) -> Optional[str] """ Resolve content types from a request. """

    for resolver in type_resolvers:
        content_type = parse_content_type(resolver(request))
        if content_type:
            return content_type