add PEP 3156, PEP 380 and PEP 492. (#90)

Author: lucas-six

recipes/core/asyncio_coroutine.md

@@ -40,3 +40,6 @@ See [source code](https://github.com/leven-cn/python-cookbook/blob/main/examples
 ## References
 
 - [Python - `asyncio` module](https://docs.python.org/3/library/asyncio.html)
+- [PEP 3156 – Asynchronous IO Support Rebooted: the "asyncio" Module](https://peps.python.org/pep-3156/)
+- [PEP 380 – Syntax for Delegating to a Subgenerator](https://peps.python.org/pep-0380/)
+- [PEP 492 – Coroutines with async and await syntax](https://peps.python.org/pep-0492/)

recipes/core/asyncio_coroutine_chain.md

@@ -39,3 +39,4 @@ See [source code](https://github.com/leven-cn/python-cookbook/blob/main/examples
 ## References
 
 - [Python - `asyncio` module](https://docs.python.org/3/library/asyncio.html)
+- [PEP 3156 – Asynchronous IO Support Rebooted: the "asyncio" Module](https://peps.python.org/pep-3156/)

recipes/core/asyncio_coroutine_concurrent.md

@@ -102,3 +102,4 @@ See [source code](https://github.com/leven-cn/python-cookbook/blob/main/examples
 ## References
 
 - [Python - `asyncio` module](https://docs.python.org/3/library/asyncio.html)
+- [PEP 3156 – Asynchronous IO Support Rebooted: the "asyncio" Module](https://peps.python.org/pep-3156/)

recipes/core/asyncio_nonblocking.md

@@ -43,3 +43,4 @@ See [source code](https://github.com/leven-cn/python-cookbook/blob/main/examples
 ## References
 
 - [Python - `asyncio` module](https://docs.python.org/3/library/asyncio.html)
+- [PEP 3156 – Asynchronous IO Support Rebooted: the "asyncio" Module](https://peps.python.org/pep-3156/)

recipes/core/asyncio_queue.md

@@ -73,3 +73,4 @@ See [source code](https://github.com/leven-cn/python-cookbook/blob/main/examples
 ## References
 
 - [Python - `asyncio` module](https://docs.python.org/3/library/asyncio.html)
+- [PEP 3156 – Asynchronous IO Support Rebooted: the "asyncio" Module](https://peps.python.org/pep-3156/)

recipes/core/asyncio_schedule.md

@@ -75,3 +75,4 @@ See [source code](https://github.com/leven-cn/python-cookbook/blob/main/examples
 ## References
 
 - [Python - `asyncio` module](https://docs.python.org/3/library/asyncio.html)
+- [PEP 3156 – Asynchronous IO Support Rebooted: the "asyncio" Module](https://peps.python.org/pep-3156/)

recipes/core/asyncio_synchronization_condition.md

@@ -58,3 +58,4 @@ See [source code](https://github.com/leven-cn/python-cookbook/blob/main/examples
 ## References
 
 - [Python - `asyncio` module](https://docs.python.org/3/library/asyncio.html)
+- [PEP 3156 – Asynchronous IO Support Rebooted: the "asyncio" Module](https://peps.python.org/pep-3156/)

recipes/core/asyncio_synchronization_event.md

@@ -51,3 +51,4 @@ See [source code](https://github.com/leven-cn/python-cookbook/blob/main/examples
 ## References
 
 - [Python - `asyncio` module](https://docs.python.org/3/library/asyncio.html)
+- [PEP 3156 – Asynchronous IO Support Rebooted: the "asyncio" Module](https://peps.python.org/pep-3156/)

recipes/core/asyncio_synchronization_lock.md

@@ -62,3 +62,4 @@ See [source code](https://github.com/leven-cn/python-cookbook/blob/main/examples
 ## References
 
 - [Python - `asyncio` module](https://docs.python.org/3/library/asyncio.html)
+- [PEP 3156 – Asynchronous IO Support Rebooted: the "asyncio" Module](https://peps.python.org/pep-3156/)

recipes/core/asyncio_synchronization_semapore.md

@@ -48,3 +48,4 @@ See [source code](https://github.com/leven-cn/python-cookbook/blob/main/examples
 ## References
 
 - [Python - `asyncio` module](https://docs.python.org/3/library/asyncio.html)
+- [PEP 3156 – Asynchronous IO Support Rebooted: the "asyncio" Module](https://peps.python.org/pep-3156/)