code: JSONStringer open(Scope empty, String openBracket) throws JSONException {
  		if (this.stack.isEmpty() && this.out.length() > 0) {
  			throw new JSONException("Nesting problem: multiple top-level roots");
  		}
  		beforeValue();
  		this.stack.add(empty);
  		this.out.append(openBracket);
  		return this;
  	}
docs: Enters a new scope by appending any necessary whitespace and the given bracket.
  @param empty any necessary whitespace
  @param openBracket the open bracket
  @return this object
  @throws JSONException if processing of json failed