requests Internals — What requests.get() Actually Does

response = requests.get('https://api.example.com/data')

What happens behind this one line:

Call Chain

requests.get(url)
  → Session().request()   # Temporary Session
    → PreparedRequest     # Assemble headers, cookies, encoding
      → HTTPAdapter.send() # Select adapter (https:// → HTTPS)
        → urllib3.PoolManager # Get connection from pool
          → socket.connect()  # Actual TCP

Why Know This

Calling requests.get() 100 times in a loop creates 100 new TCP connections. Using Session directly reuses the connection pool.

urllib3 — The Engine

requests delegates all HTTP protocol handling to urllib3. Connection pooling, Keep-Alive, retries, SSL — all urllib3 level. requests just adds a "user-friendly API" on top.

Fine Control with HTTPAdapter

Control pool size, retry count/interval, max concurrent connections.