Is the HTTP fundamentals with requests lesson free?

Yes. The first 5 lessons on PyRun are free forever — no signup, no card. HTTP fundamentals with requests runs real Python in your browser via Pyodide.

How long does the HTTP fundamentals with requests lesson take?

About 12 minutes end-to-end. It's a hands-on lesson — you read a paragraph, edit the code, and run it in the same tab.

Do I need to install Python to try the HTTP fundamentals with requests lesson?

No install required. PyRun runs real CPython in your browser via Pyodide (Python compiled to WebAssembly). Works on Chrome, Firefox, Safari, and Edge — desktop or mobile.

What level is the HTTP fundamentals with requests lesson?

Advanced level. Assumes comfort with classes, functions, and standard library. Not for first-time Python learners.

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Advanced·12 min·web · http · requests

HTTP fundamentals with requests

Every web app is just programs talking over HTTP. requests is the standard Python client — clean API, sensible defaults.

The verbs you'll actually use

GET — read. Query string via params=.
POST — create / submit. Body via json= (auto-sets Content-Type) or data= (form-encoded).
PUT / PATCH — update.
DELETE — remove.

Reading the response

r.status_code — 200 OK, 404 not found, 500 server error, 401 unauth, 429 rate-limited.
r.json() — parse JSON body (raises if not JSON).
r.text — raw string body.
r.headers — response headers dict.

Things that bite

Always set a timeout: requests.get(url, timeout=10). Otherwise a hung server hangs your program.
Use r.raise_for_status() to turn 4xx/5xx into exceptions instead of silently succeeding.
Session pooling: s = requests.Session() — reuses TCP connections, huge speedup for many calls to the same host.

Try it

Call https://httpbin.org/status/500 and observe the status_code.
Set a header {"X-PyRun": "hello"} and echo it back from /headers.

Practice

3 graded exercises

Write the code, click Check. We’ll tell you exactly what to fix.

Progress0 / 3

Exercise 1
Make a GET request to https://httpbin.org/get using requests and print r.status_code. In Pyodide, you must call pyodide_http.patch_all() before using requests — the starter does this for you.
Exercise 2
Send a GET to https://httpbin.org/get with query params {"q": "python"}. Parse the JSON response and print r.json()["args"]["q"] — httpbin echoes the query string back under args.
Exercise 3
POST to https://httpbin.org/post with json={"hello": "world"}. httpbin echoes the parsed JSON body back under the json key. Print r.json()["json"] — it should be the dict {"hello": "world"}.

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HTTP fundamentals with requests

Every web app is just programs talking over HTTP. requests is the standard Python client — clean API, sensible defaults.

The verbs you'll actually use

GET — read. Query string via params=.
POST — create / submit. Body via json= (auto-sets Content-Type) or data= (form-encoded).
PUT / PATCH — update.
DELETE — remove.

Reading the response

r.status_code — 200 OK, 404 not found, 500 server error, 401 unauth, 429 rate-limited.
r.json() — parse JSON body (raises if not JSON).
r.text — raw string body.
r.headers — response headers dict.

Things that bite

Always set a timeout: requests.get(url, timeout=10). Otherwise a hung server hangs your program.
Use r.raise_for_status() to turn 4xx/5xx into exceptions instead of silently succeeding.
Session pooling: s = requests.Session() — reuses TCP connections, huge speedup for many calls to the same host.

Try it

Call https://httpbin.org/status/500 and observe the status_code.
Set a header {"X-PyRun": "hello"} and echo it back from /headers.

Practice

3 graded exercises

Write the code, click Check. We’ll tell you exactly what to fix.

Progress0 / 3

Exercise 1
Make a GET request to https://httpbin.org/get using requests and print r.status_code. In Pyodide, you must call pyodide_http.patch_all() before using requests — the starter does this for you.
Exercise 2
Send a GET to https://httpbin.org/get with query params {"q": "python"}. Parse the JSON response and print r.json()["args"]["q"] — httpbin echoes the query string back under args.
Exercise 3
POST to https://httpbin.org/post with json={"hello": "world"}. httpbin echoes the parsed JSON body back under the json key. Print r.json()["json"] — it should be the dict {"hello": "world"}.