Implemented S3 Public Access Block

moto/s3/exceptions.py

@@ -323,3 +323,27 @@ class BucketSignatureDoesNotMatchError(S3ClientError):
             *args,
             **kwargs
         )
+
+
+class NoSuchPublicAccessBlockConfiguration(S3ClientError):
+    code = 404
+
+    def __init__(self, *args, **kwargs):
+        super(NoSuchPublicAccessBlockConfiguration, self).__init__(
+            "NoSuchPublicAccessBlockConfiguration",
+            "The public access block configuration was not found",
+            *args,
+            **kwargs
+        )
+
+
+class InvalidPublicAccessBlockConfiguration(S3ClientError):
+    code = 400
+
+    def __init__(self, *args, **kwargs):
+        super(InvalidPublicAccessBlockConfiguration, self).__init__(
+            "InvalidRequest",
+            "Must specify at least one configuration.",
+            *args,
+            **kwargs
+        )