Examines module_parameters and maps the Technology key for the CEC
        database and the Material key for the Sandia database to a common
        list of strings for cell type.

        Returns
        -------
        cell_type: str

def _infer_cell_type(self):

        """
        Examines module_parameters and maps the Technology key for the CEC
        database and the Material key for the Sandia database to a common
        list of strings for cell type.

        Returns
        -------
        cell_type: str

        """

        _cell_type_dict = {'Multi-c-Si': 'multisi',
                           'Mono-c-Si': 'monosi',
                           'Thin Film': 'cigs',
                           'a-Si/nc': 'asi',
                           'CIS': 'cigs',
                           'CIGS': 'cigs',
                           '1-a-Si': 'asi',
                           'CdTe': 'cdte',
                           'a-Si': 'asi',
                           '2-a-Si': None,
                           '3-a-Si': None,
                           'HIT-Si': 'monosi',
                           'mc-Si': 'multisi',
                           'c-Si': 'multisi',
                           'Si-Film': 'asi',
                           'EFG mc-Si': 'multisi',
                           'GaAs': None,
                           'a-Si / mono-Si': 'monosi'}

        if 'Technology' in self.module_parameters.keys():
            # CEC module parameter set
            cell_type = _cell_type_dict[self.module_parameters['Technology']]
        elif 'Material' in self.module_parameters.keys():
            # Sandia module parameter set
            cell_type = _cell_type_dict[self.module_parameters['Material']]
        else:
            cell_type = None

        return cell_type