question

example.py

def make_readonly_field_for_instance(
    parent_obj, obj, template_path: str = "", extra_context: dict = None
) -> callable:
    """
    Dynamically creating new read-only fields for ModelAdmin classes
    :param parent_obj: Models instance from admin class
    :param obj: The object for which we are creating the field
    :param template_path: Template for rendering
    :param extra_context: dynamic context
    :return: callable
    """

    def new_readonly_field(parent_obj, *args, **kwargs):
        """
        Generate ModelAdmin field for display custom HTML
        :param parent_obj: Instance from ModelAdmin
        :return: callable
        """
        
        engine_template = Engine(
            app_dirs=True,
            libraries={
                "static": "django.templatetags.static",
                "i18n": "django.templatetags.i18n",
            },
        ).get_template(template_path)

        context = Context(
            {
                "current_object": obj,
                "parent_obj": parent_obj,
                **extra_context,
            }
        )
        return engine_template.render(context)

    return new_readonly_field

class MyAdmin(admin.ModelAdmin):
    ...
    def get_fields(self, request, obj=None):
        fields = super(InvoiceAdmin, self).get_fields(request, obj)

        if obj is None:
            return fields
        fields = list(fields) if not isinstance(fields, list) else fields

        # Add dynamic readonly fields for display PDF and Email buttons
        templates_list = obj.status.templates.filter(
            api_id__isnull=False, is_active=True
        ).all()
        email_templates = EmailTemplateService().get_email_templates()
        print(email_templates)
        if len(templates_list) == 0:
            return fields

        """
        Generate HTML with links to generate PDF-file and links to send emails.
        
        Add new methods for the admin class by the number of templates
        """
        template_path = "invoice/admin/invoice_pdf_buttons_form_row.html"
        for template in templates_list:
            name_method = f"get_template_{template.pk}"

            # Create new field
            new_readonly_field = make_readonly_field_for_instance(
                obj,
                template,
                template_path,
                extra_context={
                    "email_templates": email_templates,
                    "datetime_now": timezone.now(),
                    "send_logs": template.invoiceemallog_pdftemplate.all()
                },
            )
            new_readonly_field.__name__ = name_method
            new_readonly_field.short_description = _(template.__str__())

            # Add new field to ModelAdmin
            self.dynamic_fields.append(name_method)
            if name_method not in fields:
                fields.insert(fields.index("get_invoice_lines_block"), name_method)
            if not hasattr(self, name_method):
                setattr(self, name_method, new_readonly_field)

        return fields