问如何关闭requests.Session()？

EN

# requests.Session
def close(self):
    """Closes all adapters and as such the session"""
    for v in self.adapters.values():
        v.close()

# requests.adapters.HTTPAdapter
def close(self):
    """Disposes of any internal state.

    Currently, this closes the PoolManager and any active ProxyManager,
    which closes any pooled connections.
    """
    self.poolmanager.clear()
    for proxy in self.proxy_manager.values():
        proxy.clear()

# urllib3.poolmanager.PoolManager
def connection_from_pool_key(self, pool_key, request_context=None):
    """
    Get a :class:`ConnectionPool` based on the provided pool key.

    ``pool_key`` should be a namedtuple that only contains immutable
    objects. At a minimum it must have the ``scheme``, ``host``, and
    ``port`` fields.
    """
    with self.pools.lock:
        # If the scheme, host, or port doesn't match existing open
        # connections, open a new ConnectionPool.
        pool = self.pools.get(pool_key)
        if pool:
            return pool

        # Make a fresh ConnectionPool of the desired type
        scheme = request_context['scheme']
        host = request_context['host']
        port = request_context['port']
        pool = self._new_pool(scheme, host, port, request_context=request_context)
        self.pools[pool_key] = pool

    return pool