What company focuses on Engine Overhaul for their principal activity?
CREATE TABLE table_42520 (
    "Company" text,
    "Type" text,
    "Principal activities" text,
    "Incorporated in" text,
    "Group's Equity Shareholding" text
)
SELECT "Company" FROM table_42520 WHERE "Principal activities" = 'engine overhaul'
Below are sql tables schemas paired with instruction that describes a task. Using valid SQLite, write a response that appropriately completes the request for the provided tables. ### Instruction: What company focuses on Engine Overhaul for their principal activity? ### Input: CREATE TABLE table_42520 (
    "Company" text,
    "Type" text,
    "Principal activities" text,
    "Incorporated in" text,
    "Group's Equity Shareholding" text
) ### Response: SELECT "Company" FROM table_42520 WHERE "Principal activities" = 'engine overhaul'