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+# mass\_s3
+
+Tool for running an operation on a bunch of objects in an S3 bucket a little
+more efficiently than some shit-fix bash scripts.
+
+The tool will list and filter the objects in a single thread then fork a handful
+of processes to make the actual calls to the AWS API.
+
+
+## Installation
+
+### Pre-requisites
+
+ * click
+ * boto3
+
+
+## Usage
+
+### put-object-acl
+
+    mass_s3 put-object-acl [-m modified_since] [-o owner] <bucket> <path> <new_acl>
+
+ * `-m modified_since`: Specify a date as `YYYY-MM-DD`, only objects modified on
+   or after this date will be updated.
+ * `-o owner`: Specify an owning account name, only objects owned by this account
+   will be updated.
+ * `bucket`: The S3 bucket to work on
+ * `path`: A path prefix to match objects against
+ * `new_acl`: The new acl set set on the matched objects. The Amazon canned ACLs
+   are: `private`, `public-read`, `public-read-write`, `authenticated-read`,
+   `aws-exec-read`, `bucket-owner-read`, `bucket-owner-full-control`