whole_func_string: function computeSignature(values, signatureScheme, signatureKey) {
    var hmac = crypto.createHmac(signatureScheme, signatureKey);
    values.forEach(function(v) {
      hmac.update(v);
    });
  
    return hmac.digest('hex');
  }
func_code_string: function computeSignature(values, signatureScheme, signatureKey) {
    var hmac = crypto.createHmac(signatureScheme, signatureKey);
    values.forEach(function(v) {
      hmac.update(v);
    });
  
    return hmac.digest('hex');
  }
func_documentation_string: A helper function to compute a signature using an hmac object.