docs: function decipher(string) {
  
          if(string) {
  
              if ( typeof pw !== 'string' || pw.length < 8 ) {
                  throw new Error('Please set a password with 8 or ' +
                      'more chars on process.env.CIPHER_UTIL_PW!');
              }
  
              if ( typeof algo !== 'string' || algo.length < 1 ) {
                  throw new Error('Please choose an algorithm' +
                      ' on process.env.CIPHER_UTIL_ALGO!');
              }
  
              var buffer = new Buffer(string, enc),
  
              iv = buffer.slice(0, ivBlock),
  
              text = buffer.slice(ivBlock),
  
              toDecipher = crypto.createDecipheriv(algo, pw, iv),
  
              deciphered = [toDecipher.update(text)];
  
              deciphered.push(toDecipher.final());
  
              return Buffer.concat(deciphered).toString(dec);
  
          }
  
          return null;
  
      }