How to use the xlsxwriter.compatibility.force_unicode function in XlsxWriter

elif isinstance(value, datetime):
                property_type = 'date'
            elif isinstance(value, int_types):
                property_type = 'number_int'
            elif isinstance(value, num_types):
                property_type = 'number'
            else:
                property_type = 'text'

        if property_type == 'date':
            value = value.strftime("%Y-%m-%dT%H:%M:%SZ")

        if property_type == 'text' and len(value) > 255:
            warn("Length of 'value' parameter exceeds Excel's limit of 255 "
                 "characters in set_custom_property(): '%s'" %
                 force_unicode(value))

        if len(name) > 255:
            warn("Length of 'name' parameter exceeds Excel's limit of 255 "
                 "characters in set_custom_property(): '%s'" %
                 force_unicode(name))

        self.custom_properties.append((name, value, property_type))

continue

                # Handle non-contiguous ranges like:
                #     (Sheet1!$A$1:$A$2,Sheet1!$A$4:$A$5).
                # We don't try to parse them. We just return an empty list.
                if sheetname.startswith('('):
                    chart.formula_data[r_id] = []
                    seen_ranges[c_range] = []
                    continue

                # Warn if the name is unknown since it indicates a user error
                # in a chart series formula.
                if sheetname not in worksheets:
                    warn("Unknown worksheet reference '%s' in range "
                         "'%s' passed to add_series()"
                         % (force_unicode(sheetname), force_unicode(c_range)))
                    chart.formula_data[r_id] = []
                    seen_ranges[c_range] = []
                    continue

                # Find the worksheet object based on the sheet name.
                worksheet = worksheets[sheetname]

                # Get the data from the worksheet table.
                data = worksheet._get_range_data(*cells)

                # TODO. Handle SST string ids if required.

                # Add the data to the chart.
                chart.formula_data[r_id] = data

                # Store range data locally to avoid lookup if seen again.

if formula.startswith('='):
            formula = formula.lstrip('=')

        # Local defined names are formatted like "Sheet1!name".
        sheet_parts = re.compile(r'^(.*)!(.*)$')
        match = sheet_parts.match(name)

        if match:
            sheetname = match.group(1)
            name = match.group(2)
            sheet_index = self._get_sheet_index(sheetname)

            # Warn if the sheet index wasn't found.
            if sheet_index is None:
                warn("Unknown sheet name '%s' in defined_name()"
                     % force_unicode(sheetname))
                return -1
        else:
            # Use -1 to indicate global names.
            sheet_index = -1

        # Warn if the defined name contains invalid chars as defined by Excel.
        if (not re.match(r'^[\w\\][\w\\.]*$', name, re.UNICODE)
                or re.match(r'^\d', name)):
            warn("Invalid Excel characters in defined_name(): '%s'"
                 % force_unicode(name))
            return -1

        # Warn if the defined name looks like a cell name.
        if re.match(r'^[a-zA-Z][a-zA-Z]?[a-dA-D]?[0-9]+$', name):
            warn("Name looks like a cell name in defined_name(): '%s'"
                 % force_unicode(name))

property_type = 'number'
            else:
                property_type = 'text'

        if property_type == 'date':
            value = value.strftime("%Y-%m-%dT%H:%M:%SZ")

        if property_type == 'text' and len(value) > 255:
            warn("Length of 'value' parameter exceeds Excel's limit of 255 "
                 "characters in set_custom_property(): '%s'" %
                 force_unicode(value))

        if len(name) > 255:
            warn("Length of 'name' parameter exceeds Excel's limit of 255 "
                 "characters in set_custom_property(): '%s'" %
                 force_unicode(name))

        self.custom_properties.append((name, value, property_type))