TutorTask555: Minor code changes and documentation

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Author: indrayudd

DATA605/TutorialsTask76_automate_collaborator_invitations_from_gsheet.explanation.md

@@ -0,0 +1,69 @@
+<!-- toc -->
+
+- [`TutorialsTask76_automate_collaborator_invitations_from_gsheet.py` Explanation](#tutorialstask76_automate_collaborator_invitations_from_gsheetpy-explanation)
+  * [Public interface](#public-interface)
+  * [Execution flow](#execution-flow)
+  * [Key implementation choices](#key-implementation-choices)
+
+<!-- tocstop -->
+
+# `TutorialsTask76_automate_collaborator_invitations_from_gsheet.py` Explanation
+
+This document is about how this script works and flows.
+
+## Public interface
+
+```bash
+TutorialsTask76_automate_collaborator_invitations_from_gsheet.py \
+    --drive_url <google‑sheet‑url>  \
+    --gh_token  <github‑pat>       \
+    --org_name  <github‑org>       \
+    --repo_name <repo>             \
+    [--log_level 20]
+```
+
+- **`drive_url`** – Spreadsheet containing a `GitHub user` column.
+- **`gh_token`** – PAT with `repo` scope (or fine‑grained "Repository
+  administration").
+- **`org_name` / `repo_name`** – identify the target repository.
+- **`log_level`** – standard Python numeric levels (10 = DEBUG, 20 = INFO).
+
+The module can also be imported:
+
+```python
+import DATA605.TutorialsTask76_automate_collaborator_invitations_from_gsheet as dtacifrgs
+usernames = dtacifrgs.extract_usernames_from_gsheet(sheet_url)
+dtacifrgs.send_invitations(usernames, token, repo, org)
+```
+
+## Execution flow
+
+```mermaid
+flowchart TD
+    A[parse CLI args] --> B[init logging]
+    B --> C[extract_usernames_from_gsheet]
+    C -->|"list[str]"| D[send_invitations]
+    D --> E{already collaborator?}
+    E -- yes --> F[skip + log]
+    E -- no --> G[_invite wrapper]
+    G -->|add_to_collaborators| H[GitHub API]
+    subgraph Rate-limit
+        direction TB
+        G
+        note("@ratelimit.limits 50 calls / 24h → sleep_and_retry if exceeded")
+    end
+```
+
+## Key implementation choices
+
+- **Dependency auto‑install** – the small `pip install` loop avoids a separate
+  requirements file when the script runs in fresh environments, at the cost of
+  start‑up time.
+- **Service‑account auth** – credentials path is hard‑coded but can be fed via
+  env‑var if desired; the helper supports both.
+- **Idempotence** – `repo.has_in_collaborators()` prevents duplicate invites
+  counting toward the daily quota.
+- **Sleep strategy** – we rely entirely on `ratelimit.sleep_and_retry`, so the
+  process may block for hours. Even if the process is terminated, the
+  idempotence measure will prevent the added names from contributing to the
+  quota

DATA605/TutorialsTask76_automate_collaborator_invitations_from_gsheet.how_to_guide.md

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+<!-- toc -->
+
+- [Inviting GitHub Collaborators from Google Sheets](#inviting-github-collaborators-from-google-sheets)
+  * [Prerequisites](#prerequisites)
+  * [Running the script](#running-the-script)
+
+<!-- tocstop -->
+
+# Inviting GitHub Collaborators from Google Sheets
+
+## Prerequisites
+
+- **GitHub personal‑access token** (PAT) with the classic **`repo`** scope, or a
+  fine‑grained token granting Repository administration for the target
+  repository.
+
+  ```bash
+  export GH_PAT=github_pat_...
+  ```
+
+- **Google service‑account JSON key**
+  - Create a service account in Google Cloud.
+  - Enable the _Drive API_ on that project.
+  - Download the key as JSON and place it at `/app/DATA605/google_secret.json`
+    (or change the path in the script).
+  - Share the spreadsheet with the service‑account address.
+
+## Running the script
+
+```bash
+python automate_collaborator_invitations.py \
+    --drive_url "https://docs.google.com/spreadsheets/d/..." \
+    --gh_token  "$GH_PAT" \
+    --org_name  causify-ai \
+    --repo_name tutorials \
+    --log_level 20          # INFO
+```
+
+- **`--drive_url`** – full URL of the Google Sheet containing a column named
+  `GitHub user`.
+- **`--gh_token`** – your PAT (or set `GH_PAT` and pass `--gh_token "$GH_PAT"`).
+- **`--org_name` / `--repo_name`** – where the invitations will be sent.
+- Increase `--log_level` to `10` for verbose debug logs.

DATA605/TutorialsTask76_automate_collaborator_invitations_from_gsheet.py

@@ -97,6 +97,9 @@ def send_invitations(
     repo = gh.get_repo(f"{org_name}/{repo_name}")
     # Send invitations.
     for username in usernames:
+        if repo.has_in_collaborators(username):
+            _LOG.info("User %s is already a collaborator", username)
+            continue
         try:
             _invite(repo, username)
         except github.GithubException as exc:
@@ -107,7 +110,7 @@ def send_invitations(
 
 def _parse() -> argparse.Namespace:
     parser = argparse.ArgumentParser(
-        description="Invite GitHub collaborators from a Google Sheet, respecting the 50‑per‑day limit.",  # noqa: E501
+        description="Invite GitHub collaborators from a Google Sheet, respecting the 50‑per‑day limit.", 
         formatter_class=argparse.ArgumentDefaultsHelpFormatter,
     )
     parser.add_argument(