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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 login(self, url=None, api_key=None, login=None, pwd=None, api_version=None, timeout=None, verify=True, alt_filepath=None, domain=None, **kwargs):
 """ Login to SMC API and retrieve a valid session. Sessions use a pool connection manager to provide dynamic scalability during times of increased load. Each session is managed by a global session manager making it possible to have more than one session per interpreter. An example login and logout session:: from smc import session session.login(url='http://1.1.1.1:8082', api_key='SomeSMCG3ener@t3dPwd') session.logout() :param str url: ip of SMC management server :param str api_key: API key created for api client in SMC :param str login: Administrator user in SMC that has privilege to SMC API. :param str pwd: Password for user login. :param api_version (optional):
 specify api version :param int timeout: (optional):
 specify a timeout for initial connect; (default 10) :param str|boolean verify: verify SSL connections using cert (default: verify=True) You can pass verify the path to a CA_BUNDLE file or directory with certificates of trusted CAs :param str alt_filepath: If using .smcrc, alternate path+filename :param str domain: domain to log in to. If domains are not configured, this field will be ignored and api client logged in to 'Shared Domain'. :param bool retry_on_busy: pass as kwarg with boolean if you want to add retries if the SMC returns HTTP 503 error during operation. You can also optionally customize this behavior and call :meth:`.set_retry_on_busy` :raises ConfigLoadError: loading cfg from ~.smcrc fails For SSL connections, you can disable validation of the SMC SSL certificate by setting verify=False, however this is not a recommended practice. If you want to use the SSL certificate generated and used by the SMC API server for validation, set verify='path_to_my_dot_pem'. It is also recommended that your certificate has subjectAltName defined per RFC 2818 If SSL warnings are thrown in debug output, see: https://urllib3.readthedocs.io/en/latest/advanced-usage.html#ssl-warnings Logout should be called to remove the session immediately from the SMC server. .. note:: As of SMC 6.4 it is possible to give a standard Administrative user access to the SMC API. It is still possible to use an API Client by providing the api_key in the login call. """

        params = {}
        if not url or (not api_key and not (login and pwd)):
            try: # First try load from file
                params = load_from_file(alt_filepath) if alt_filepath\
                    is not None else load_from_file()
                logger.debug('Read config data from file: %s', params)
            except ConfigLoadError:
                # Last ditch effort, try to load from environment
                params = load_from_environ()
                logger.debug('Read config data from environ: %s', params)
        
        params = params or dict(
            url=url,
            api_key=api_key,
            login=login,
            pwd=pwd,
            api_version=api_version,
            verify=verify,
            timeout=timeout,
            domain=domain,
            kwargs=kwargs or {})
        
        # Check to see this session is already logged in. If so, return.
        # The session object represents a single connection. Log out to
        # re-use the same session object or get_session() from the
        # SessionManager to track multiple sessions.
        if self.manager and (self.session and self in self.manager):
            logger.info('An attempt to log in occurred when a session already '
                'exists, bypassing login for session: %s' % self)
            return
        
        self._params = {k: v for k, v in params.items() if v is not None}
        
        verify_ssl = self._params.get('verify', True)
        
        # Determine and set the API version we will use.
        self._params.update(
            api_version=get_api_version(
                self.url, self.api_version, self.timeout, verify_ssl))
        
        extra_args = self._params.get('kwargs', {})
        
        # Retries configured
        retry_on_busy = extra_args.pop('retry_on_busy', False)
        
        request = self._build_auth_request(verify_ssl, **extra_args)
            
        # This will raise if session login fails...
        self._session = self._get_session(request)
        self.session.verify = verify_ssl

        if retry_on_busy:
            self.set_retry_on_busy()
        
        # Load entry points
        load_entry_points(self)
        
        # Put session in manager
        self.manager._register(self)
        
        logger.debug('Login succeeded for admin: %s in domain: %s, session: %s',
            self.name, self.domain, self.session_id)