text: class PhoneNumberValidator {
      static validateMobilePhoneNumber(num) {
          const ukNumberMatchRE = new RegExp(/^7[0-9]{9}$/);
          const ukPrefix = '44';
          const internationalMatchRE = new RegExp(/^[0-9]*$/);
  
          if (num.startsWith('+')) {
              let toValidate = num.slice(1);
              if (toValidate.startsWith(ukPrefix)) {
                  toValidate = toValidate.slice(2);
                  if (toValidate.match(ukNumberMatchRE)) {
                      return true;
                  }
              } else if (toValidate.match(internationalMatchRE)) {
                  return true;
              }
          }
  
          if (num.startsWith('07')) {
              const toValidate = num.slice(1);
              if (toValidate.match(ukNumberMatchRE)) {
                  return true;
              }
          }
  
          return false;
      }
  }
  
  module.exports = PhoneNumberValidator;
  