code: public static Fixture parseFrom(String fileName, Parser parser) {
      if (fileName == null) {
        throw new NullPointerException("File name should not be null");
      }
      String path = "fixtures/" + fileName + ".yaml";
      InputStream inputStream = openPathAsStream(path);
      Fixture result = parser.parse(inputStream);
  
      if (result.body != null && !result.body.startsWith("{")) {
        String bodyPath = "fixtures/" + result.body;
        try {
          result.body = readPathIntoString(bodyPath);
        } catch (IOException e) {
          throw new IllegalStateException("Error reading body: " + bodyPath, e);
        }
      }
      return result;
    }
docs: Parse the given filename and returns the Fixture object.
  
  @param fileName filename should not contain extension or relative path. ie: login
  @param parser   parser is required for parsing operation, it should not be null