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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 check_for_env_url(self):
 """ First checks to see if a url argument was explicitly passed in. If so, that will be used. If not, it checks for the existence of the environment variable specified in ENV_URL. If this is set, it should contain a fully qualified URL to the service you want to use. Note that any values passed explicitly to the class constructor will take precedence. """

        url = self.args.get('url', None)
        if url:
            del self.args['url']
        if not url and self.EnvURL in os.environ:
            url = os.environ[self.EnvURL]
        if url:
            rslt = urlparse.urlparse(url)
            if 'is_secure' not in self.args:
                if rslt.scheme == 'https':
                    self.args['is_secure'] = True
                else:
                    self.args['is_secure'] = False

            host = rslt.netloc
            port = None
            l = host.split(':')
            if len(l) > 1:
                host = l[0]
                port = int(l[1])
            if 'host' not in self.args:
                self.args['host'] = host
            if port and 'port' not in self.args:
                self.args['port'] = port

            if rslt.path and 'path' not in self.args:
                self.args['path'] = rslt.path