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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 get_url(self, datatype, verb, urltype, params={}, api_host=None, api_version=None):
 """Returns a fully formed url :param datatype: a string identifying the data the url will access. :param verb: the HTTP verb needed for use with the url. :param urltype: an adjective used to the nature of the request. :param \*\*params: substitution variables for the URL. :return: string :rtype: A fully formed url. """

        api_version = api_version or 'v1'
        api_host = api_host or self.host

        subst = params.copy()
        subst['api_host'] = api_host
        subst['api_version'] = api_version

        url = "https://{api_host}/services/api/{api_version}"
        url += self.get_url_path(datatype, verb, urltype, params, api_version)
        return url.format(**subst)