Create pr_fetcher.py

pr_fetcher.py

@@ -0,0 +1,28 @@
+import requests
+
+def fetch_pr_diff(repo_owner, repo_name, pr_number, github_token):
+    """
+    Fetches the diff of a pull request from a GitHub repository.
+
+    Args:
+        repo_owner (str): The owner of the GitHub repository.
+        repo_name (str): The name of the GitHub repository.
+        pr_number (int): The pull request number.
+        github_token (str): A personal access token for GitHub API.
+
+    Returns:
+        str: The diff text of the pull request, or an error message.
+    """
+    headers = {
+        "Accept": "application/vnd.github.v3.diff",
+        "Authorization": f"Bearer {github_token}"
+    }
+
+    url = f"https://api.github.com/repos/{repo_owner}/{repo_name}/pulls/{pr_number}"
+
+    response = requests.get(url, headers=headers)
+
+    if response.status_code == 200:
+        return response.text
+    else:
+        return f"Error {response.status_code}: {response.text}"