Create a dictionary representation of a PWInput object
        
        Returns:
            dict

def as_dict(self):
        """
        Create a dictionary representation of a PWInput object
        
        Returns:
            dict
        """
        pwinput_dict = {'structure': self.structure.as_dict(),
                        'pseudo': self.pseudo,
                        'sections': self.sections,
                        'kpoints_mode': self.kpoints_mode,
                        'kpoints_grid': self.kpoints_grid,
                        'kpoints_shift': self.kpoints_shift}
        return pwinput_dict