def file_length
      if self.audio.is_a?(File) && self.audio.size > MAX_FILE_SIZE
        self.errors.add :audio, "It's length is excesive. #{MAX_FILE_SIZE} is the limit."
        return false
      end

      return true
    end
def file_length
      if self.audio.is_a?(File) && self.audio.size > MAX_FILE_SIZE
        self.errors.add :audio, "It's length is excesive. #{MAX_FILE_SIZE} is the limit."
        return false
      end

      return true
    end
Function to check that the file size isn't excesive.