Types: 
- q: int
- query_i: Tuple[int, str, Optional[int]] for i in 1 to q

Ranges:
- 1 ≤ q ≤ 200,000
- 1 ≤ x ≤ 1,000,000,000
- 1 ≤ length of key ≤ 20
- key consists of lower-case letters
- L ≤ R in lexicographic order

Addtl Info: 
- The total number of elements printed by dump operations does not exceed 1,000,000