How to use the notion.markdown.markdown_to_notion function in notion

def _convert_python_to_notion(self, val, prop, identifier=""):

        if prop["type"] in ["title", "text"]:
            if not val:
                val = ""
            if not isinstance(val, str):
                raise TypeError(
                    "Value passed to property '{}' must be a string.".format(identifier)
                )
            val = markdown_to_notion(val)
        if prop["type"] in ["number"]:
            if val is not None:
                if not isinstance(val, float) and not isinstance(val, int):
                    raise TypeError(
                        "Value passed to property '{}' must be an int or float.".format(
                            identifier
                        )
                    )
                val = [[str(val)]]
        if prop["type"] in ["select"]:
            if not val:
                val = None
            else:
                valid_options = [p["value"].lower() for p in prop["options"]]
                val = val.split(",")[0]
                if val.lower() not in valid_options:

data["start_time"] = start_time or "00:00"
            if end_date:
                data["end_time"] = end_time or "00:00"

        return [["‣", [["d", data]]]]


class Collection(Record):
    """
    A "collection" corresponds to what's sometimes called a "database" in the Notion UI.
    """

    _table = "collection"

    name = field_map(
        "name", api_to_python=notion_to_markdown, python_to_api=markdown_to_notion
    )
    description = field_map(
        "description",
        api_to_python=notion_to_markdown,
        python_to_api=markdown_to_notion,
    )
    cover = field_map("cover")

    @property
    def templates(self):
        if not hasattr(self, "_templates"):
            template_ids = self.get("template_pages", [])
            self._client.refresh_records(block=template_ids)
            self._templates = Templates(parent=self)
        return self._templates

class Collection(Record):
    """
    A "collection" corresponds to what's sometimes called a "database" in the Notion UI.
    """

    _table = "collection"

    name = field_map(
        "name", api_to_python=notion_to_markdown, python_to_api=markdown_to_notion
    )
    description = field_map(
        "description",
        api_to_python=notion_to_markdown,
        python_to_api=markdown_to_notion,
    )
    cover = field_map("cover")

    @property
    def templates(self):
        if not hasattr(self, "_templates"):
            template_ids = self.get("template_pages", [])
            self._client.refresh_records(block=template_ids)
            self._templates = Templates(parent=self)
        return self._templates

    def get_schema_properties(self):
        """
        Fetch a flattened list of all properties in the collection's schema.
        """
        properties = []

def py2api(x):
        x = python_to_api(x)
        if markdown:
            x = markdown_to_notion(x)
        return x