function array_replace_key($search, $replace, array $subject) {     $updatedArray = [];      foreach ($subject as $key => $value) {         if (!is_array($value) && $key == $search) {             $updatedArray = array_merge($updatedArray, [$replace => $value]);                          continue;         }          $updatedArray = array_merge($updatedArray, [$key => $value]);     }      return $updatedArray; }  $user = ['name' => 'Donald Pakkies', 'age' => 22];  var_dump(array_replace_key('name', 'full_name', $user));

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