Custom odoo wizard for import data

I want to create a custom wizard that imports a csv and then compares this data to the data that is already in the database. I then want to select to keep the data, replace or delete the data. i am currently on Odoo8.

I currently have:

class ExcelImport(models.TransientModel):
    _name = 'excell.import.wizard'

   

     excel_file_for_import = fields.Binary(string='File for upload')
    
        def import_data_form_file(self):
            try:
                inputx = StringIO.StringIO()
                inputx.write(base64.decodestring(self.excel_file_for_import))
                book = open_workbook(file_contents=inputx.getvalue())
            except TypeError as e:
                raise ValidationError(u'ERROR: {}'.format(e))
            sheet = book.sheets()[0]
    
            for i in range(sheet.nrows):
                if i == 0:
                    continue
                if i == 1:
                    name = sheet.cell(i, 0).value
                    vat = sheet.cell(i, 5).value