def strip_literal(literal)
      literal = literal[1..-1] if literal[0] == ':'
      literal = literal[1..-2] if literal[0] == "'" || literal[0] == '"'
      literal
    end
def strip_literal(literal)
      literal = literal[1..-1] if literal[0] == ':'
      literal = literal[1..-2] if literal[0] == "'" || literal[0] == '"'
      literal
    end
remove the leading colon and unwrap quotes from the key match
 @param literal [String] e.g: "key", 'key', or :key.
 @return [String] key