Constructor to build an AmiraHeader object from a file
        
        :param str fn: Amira file
        :return ah: object of class ``AmiraHeader`` containing header metadata
        :rtype: ah: :py:class:`ahds.header.AmiraHeader`

def from_file(cls, fn, *args, **kwargs):
        """Constructor to build an AmiraHeader object from a file
        
        :param str fn: Amira file
        :return ah: object of class ``AmiraHeader`` containing header metadata
        :rtype: ah: :py:class:`ahds.header.AmiraHeader`
        """
        return AmiraHeader(get_parsed_data(fn, *args, **kwargs))