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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 _send_post(self, blogname, params):
 """ Formats parameters and sends the API request off. Validates common and per-post-type parameters and formats your tags for you. :param blogname: a string, the blogname of the blog you are posting to :param params: a dict, the key-value of the parameters for the api request :param valid_options: a list of valid options that the request allows :returns: a dict parsed from the JSON response """

        url = "/v2/blog/{}/post".format(blogname)
        valid_options = self._post_valid_options(params.get('type', None))

        if len(params.get("tags", [])) > 0:
            # Take a list of tags and make them acceptable for upload
            params['tags'] = ",".join(params['tags'])

        return self.send_api_request("post", url, params, valid_options)