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function is not described

Requests::flattern() public WP 1.0

Deprecated. It is no longer supported and can be removed in future releases. See Requests::flatten}.

Convert a key => value array to a 'key: value' array for headers

{} It's a method of the class: Requests{}

No Hooks.

Return

String[]. List of headers

Usage

$result = Requests::flattern( $array );
$array(array) (required)
Dictionary of header values

Changelog

Deprecated Misspelling of {@see Requests::flatten}

Code of Requests::flattern() WP 5.7.1

<?php
public static function flattern($array) {
	return self::flatten($array);
}