```ruby
module MIPS
  class Assembler
  end
end
```

Add basic structure for Assembler.
user
```ruby
module MIPS
  # Assembly MIPS codes into machine codes.
  class Assembler
    attr_reader :symbol_table

    def initialize
      @symbol_table = {}
    end

    def assembly(line)
      0x0
    end

    def self.assembly(line)
      new.assembly(line)
    end
  end
end
```
assistant