docs: function validate(address, address_type) {
      // default is to check that address is regular production address
      address_type = address_type || 'prod';
  
      var type = get_address_type(address);
      if (type === null) {
          return false;
      }
  
      if (type !== address_types[address_type] &&
          type !== p2sh_types[address_type]) {
          return false;
      }
  
      return true;
  }