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## 1.57.10

**`(fix):`** Optional idempotency headers are no longer sent with a Go expression prefix
prepended to their value. An `optional<string>` idempotency header was sent
with a literal `*` in front of the caller's value, and an
`optional<base64>` one with a literal `base64.StdEncoding.EncodeToString(`,
because the dereference/encode prefix used to build the value expression was
also interpolated into the `fmt.Sprintf` format string. Required headers were
unaffected.