Add links

Author: pablogsal

peps/pep-0778.rst

@@ -55,7 +55,8 @@ counting system. This combination of low-level system manipulation and
 deep domain specific interpreter knowledge makes implementing Python debugging tools
 exceptionally difficult.
 
-The few tools that do attempt this resort to suboptimal and unsafe methods,
+The few tools ( see for example [1]_ and [2]_ )that do attempt this resort to
+suboptimal and unsafe methods,
 using system debuggers like gdb and lldb to forcefully inject code. This
 approach is fundamentally unsafe because the injected code can execute at any
 point during the interpreter's execution cycle - even during critical operations
@@ -342,6 +343,15 @@ Reference Implementation
 https://github.com/pablogsal/cpython/commits/remote_pdb/
 
 
+References
+==========
+
+.. [1] DebugPy
+   https://github.com/microsoft/debugpy/blob/43f41029eabce338becbd1fa1a09727b3cfb1140/src/debugpy/_vendored/pydevd/pydevd_attach_to_process/linux_and_mac/attach.cpp#L4
+
+.. [2] Memray
+   https://github.com/bloomberg/memray/blob/main/src/memray/_memray/inject.cpp
+
 Copyright
 =========