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+# Codebase Summary: `google-cloud-storage`
+
+This document provides a high-level overview of the main components of the Google Cloud Storage Python client library.
+
+## Main Components
+
+### 1. Client (`google/cloud/storage/client.py`)
+The `Client` class is the entry point for interacting with the Google Cloud Storage API. It handles authentication and project configuration.
+- **Key Responsibilities**:
+    - Authenticating with Google Cloud.
+    - Creating, retrieving, and listing buckets.
+    - Managing batch operations.
+    - Creating HMAC keys.
+
+### 2. Bucket (`google/cloud/storage/bucket.py`)
+The `Bucket` class represents a Google Cloud Storage bucket. It provides methods to manage the bucket itself and the objects (blobs) within it.
+- **Key Responsibilities**:
+    - Creating and deleting the bucket.
+    - Configuring bucket properties (ACLs, lifecycle rules, versioning, CORS, website configuration, etc.).
+    - Creating, listing, getting, and deleting blobs.
+    - Managing IAM policies for the bucket.
+
+### 3. Blob (`google/cloud/storage/blob.py`)
+The `Blob` class represents an object (file) within a GCS bucket. It provides methods to upload, download, and manage the object.
+- **Key Responsibilities**:
+    - Uploading data (from file, filename, or string).
+    - Downloading data (to file, filename, bytes, or text).
+    - Managing object metadata and ACLs.
+    - Deleting the object.
+    - Generating signed URLs for temporary access.
+
+### 4. Batch (`google/cloud/storage/batch.py`)
+The `Batch` class allows grouping multiple API calls into a single HTTP request. This is useful for performing multiple operations (like patching or deleting multiple blobs) efficiently.
+- **Key Responsibilities**:
+    - Accumulating multiple requests.
+    - Sending them in a single `multipart/mixed` HTTP request.
+    - Processing the responses.
+
+### 5. Transfer Manager (`google/cloud/storage/transfer_manager.py`)
+The `transfer_manager` module provides utilities for concurrent uploads and downloads, which can significantly improve performance for large numbers of files or large files.
+- **Key Responsibilities**:
+    - `upload_many` / `upload_many_from_filenames`: Uploading multiple files concurrently.
+    - `download_many` / `download_many_to_path`: Downloading multiple blobs concurrently.
+    - `download_chunks_concurrently`: Downloading a single large file in chunks concurrently.
+    - `upload_chunks_concurrently`: Uploading a single large file in chunks concurrently (using XML Multi-Part Upload).
+
+## Directory Structure
+
+- `google/cloud/storage/`: Contains the source code for the library.
+- `tests/`: Contains unit and system tests.
+- `samples/`: Contains code samples demonstrating how to use the library.