public Optional<NumberNode> getNumberMember(String memberName) {
        return getMember(memberName)
                .map(n -> n.expectNumberNode(() -> format("Expected `%s` to be a number; found {type}", memberName)));
    }
Gets the member with the given name, and if present, expects it to
be a number.

@param memberName Name of the member to get.
@return Returns the optional node with the given member name.
@throws ExpectationNotMetException if the member is not a number.
smithy-model/src/main/java/software/amazon/smithy/model/node/ObjectNode.java