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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _split_markdown(text_url, tld_pos):
 """ Split markdown URL. There is an issue wen Markdown URL is found. Parsing of the URL does not stop on right place so wrongly found URL has to be split. :param str text_url: URL that we want to extract from enclosure :param int tld_pos: position of TLD :return: URL that has removed enclosure :rtype: str """

        # Markdown url can looks like:
        # [http://example.com/](http://example.com/status/210)

        left_bracket_pos = text_url.find('[')
        # subtract 3 because URL is never shorter than 3 characters
        if left_bracket_pos > tld_pos-3:
            return text_url

        right_bracket_pos = text_url.find(')')
        if right_bracket_pos < tld_pos:
            return text_url

        middle_pos = text_url.rfind("](")
        if middle_pos > tld_pos:
            return text_url[left_bracket_pos+1:middle_pos]
        return text_url