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function framework_check_extension_usage($exten=true) {  global $active_modules;  static $cached_extens;    if (!$cached_extens) {    // call all module _check_extens() hooks    $cached_extens = array();    foreach(array_keys($active_modules) as $key) {      $function = $key."_check_extensions";      if (function_exists($function)) {        $cached_extens[$key] = $function());      }    }  }    if ($exten === true) {    // return ALL extensions    return $cached_extens;  } else {    // look for a list of extens    if (!is_array($exten)) { $exten = array($exten); }    $exten_matches = array();        foreach (array_keys($cached_extens) as $key) {      foreach ($exten as $test_exten) {        if (isset($cached_extens[$key][$text_exten])) {          $exten_matches[$key][$test_exten] = $cached_extens[$key][$text_exten];        }      }    }    return $exten_matches;  }}