Fix push over https.
Without this patch, python gives me a
TypeError: write() argument 1 must be string or read-only buffer, not file
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1 files, 1 changesets, 1 total revisions
checking changesets
checking manifests
crosschecking files in changesets and manifests
checking files
verify failed
checking changesets
checking manifests
crosschecking files in changesets and manifests
checking files
1 files, 1 changesets, 1 total revisions
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