code: public function isAcademic($text)
      {
          if (empty($text)) {
              return false;
          }
  
          $domain = $this->getDomain($text);
  
          if ($domain === null) {
              return false;
          }
  
          foreach ($this->getBlacklistedTopLevelDomains() as $blacklistedDomain) {
              $name = (string) $domain['host'];
  
              if (preg_match('/' . preg_quote($blacklistedDomain) . '$/', $name)) {
                  return false;
              }
          }
  
          if (in_array($domain['tld'], $this->getAcademicTopLevelDomains())) {
              return true;
          }
  
          if ($this->matchesAcademicDomain($domain)) {
              return true;
          }
  
          return false;
      }
docs: Determines whether or not an email address or domain is
  part of a higher-education institution.
  
  @param  string $text Email address or domain name
  @return bool   true if academic, false otherwise