Extract the data from the request
        :param data: A mult-dict with either the post or get query

def extract_value(self, data):
        """
        Extract the data from the request
        :param data: A mult-dict with either the post or get query
        """
        if self.name not in data and not self.allow_missing:
            raise exceptions.FieldNotFound('Field {} is missing from request'.format(self.name))
        
        if self.multiple_inputs:
            self.value = []
            for value in data.getlist(self.name):
                if self.strip_value:
                    value = value.strip()
                if value == '' and self.convert_empty_to_none:
                    value = None

                self.value.append(value)
        else:
            self.value = data.get(self.name)
            if self.value is not None:
                if self.strip_value:
                    self.value = self.value.strip()
                if self.value == '' and self.convert_empty_to_none:
                    self.value = None

        # Convert the value to the correct data type
        self.convert_value()