code: function parseValueToStringOrNumber ( value ) {
  	let resolvedValue, resolvedUnitValue;
  	try {
  		resolvedUnitValue = parseUnit(value);
  		if ( unitTypes.indexOf(resolvedUnitValue.type) !== -1 ) {
  			resolvedValue = new types.Number(resolvedUnitValue.value, resolvedUnitValue.unit);
  		} else if ( resolvedUnitValue.type === 'percentage' ) {
  			resolvedValue = new types.Number(resolvedUnitValue.value, '%');
  		} else {
  			resolvedValue = new types.String(resolvedUnitValue.value);
  		}
  	} catch ( e ) {
  		resolvedValue = new types.String(value);
  	}
  	return resolvedValue;
  }
docs: @param  {String} value
  
  @return {sass.types.String|sass.types.Number}