The loop including line 3 of the listing is working through the keys received, getting a corresponding value, and printing it as an array or a string.

包含清单第3行的循环将遍历接收到的键，获得相应值，并把它作为数组或字符串输出。

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He received the gold master-keys of the Tower from the Lord Chamberlain, symbolising his responsibility for the royal palace.

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Rather, Keys tweeted a copy of a "final written warning" he said he received from Reuters in October, which admonished him for unprofessional behavior after he mocked a Google executive from a fake Twitter account.

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He received 54 honorary degrees, while some 500 towns presented him with their keys.

ECONOMIST: Bob Hope