Gsutil

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Bug Fixes
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- Improve content type inference for some common extensions. (1321)
- Copy Content-Encoding from first object in compose command. (1320)
- Support generation querying for ls command. (1319)

Other Changes
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- Add a message encouraging py3 upgrade. (1322)
- Update mock library version. (1315)
- Several documentation updates and clarifications.

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Bug Fixes
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- Update pyu2f to latest version to fix a security key reauth bug (1310)

Other Changes
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- Several documentation updates and clarifications.

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New Features
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- Onboard mTLS support with AIP-4114 for gsutil (1302)

Other Changes
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- Several documentation updates and clarifications.

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New Features
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- Add gsutil support for Public Access Prevention (1255)

Bug Fixes
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- Fix raising-bad-type yapf errors. (1303)

Other Changes
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- Link fix pointing to CGC docs again (1291).
- Backfill some small doc changes (1294)
- Small text tweak (1293)
- Update CHECKSUM and VERSION for 4.64 release.
- Update CHANGES.md for 4.64 release.
- Delete encryption addhelp page (1297)
- Putting cl/381035251 into github (1296)
- Backfill cl/381932961 (1298)

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Bug Fixes
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- None

Other Changes
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- Link fix pointing to CGC docs.

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Bug Fixes
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- Update warning text on KMS access denied (1278)
- Make ** to represent zero or more folders for cloud urls (1277)
- Raise error if final destination path ends with a delimiter. (1273)

Other Changes
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- Fix flaky test for rm using preconditions (1288)
- Fix pyenv issue for macOS (1280)
- Fix rewrite tests (1279)
- Remove unused progress callback. (1274)
- Several documentation updates and clarifications.