class SimpleTemplate:
    def __init__(self, template: str):
        self.template: str = template

    def render(self, context):
        # Loop through context items
        ret = self.template
        for key, value in context.items():
            if key.startswith("loop:"):
                # If the key starts with "loop:", handle loop processing
                loop_name = key[len("loop:"):]
                start = f"{{{{loop:variable.{loop_name} as item}}}}"
                end = f"{{{{end_loop:variable.{loop_name}}}}}"
                if start not in ret:
                    continue
                idx_start = ret.index(start) + len(start)
                idx_end = ret.index(end)
                template_child = ret[idx_start:idx_end]
                ret = ret[:(idx_start - len(start))] + ret[idx_end:]
                loop_content = ""
                for item in value:
                    loop_content += self.render_columns(template_child, item)
                ret = ret.replace(end, loop_content)
            else:
                # If not a loop, replace the placeholder with the value
                value = str(value).replace('\n', '<br>') if value not in [False, None] else ''
                ret = ret.replace(f"{{{{variable.{key}}}}}", str(value))
        return ret

    def render_columns(self, child_template: str, item: dict):
        for k, v in item.items():
            child_template = child_template.replace(
                f"{{{{item.{k}}}}}",
                str(v).replace('\n', '<br>') if v not in [False, None] else ''
            )
        return child_template