```python
self.idx_to_token = list(sorted(set(
  ['<unk>'] + reserved_tokens + map(
    lambda token, _: token,
    filter(
	  lambda _, freq: freq >= min_freq,
	  self.token_freqs
	)
  )
)))
```
```python
self.idx_to_token = list(sorted(set(
  ['<unk>'] + reserved_tokens + map(
    lambda token, _: token,
    filter(
	  lambda _, freq: freq >= min_freq,
	  self.token_freqs
	)
  )
)))
```