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vendor/fig/http-message-util/README.md

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+# PSR Http Message Util
+
+This repository holds utility classes and constants to facilitate common
+operations of [PSR-7](https://www.php-fig.org/psr/psr-7/); the primary purpose is
+to provide constants for referring to request methods, response status codes and
+messages, and potentially common headers.
+
+Implementation of PSR-7 interfaces is **not** within the scope of this package.
+
+## Installation
+
+Install by adding the package as a [Composer](https://getcomposer.org)
+requirement:
+
+```bash
+$ composer require fig/http-message-util
+```