added installing solcx version

chronological-issues-from-video.md

@@ -6,3 +6,13 @@ This file will list issues/updates by timestamp. If you have an issue that you d
 - [2:37:05](https://youtu.be/M576WGiDBdQ?t=9425) Kovan vs Rinkeby
   - Our `FundMe.sol` needs to be deployed to the *rinkeby* chain to work, but if you go to try the price feeds from the Chainlink docs using the remix link, that one has the *kovan* price feeds in it, so needs to be deployed to kovan. 
   - If you want to test the price feeds from the video using the Chainlink docs remix link, you'll need to follow the steps to [get kovan ETH](https://docs.chain.link/docs/link-token-contracts/#kovan).  
+
+## Lesson 4:
+- [3:43:52](https://youtu.be/M576WGiDBdQ?t=13432) Installing solcx version 0.6.0
+  - In the video, we forgot to do 2 things in order to compile our solidity code:
+    - Import `install_solc`, so we need to change this line:
+      - `from solcx import compile_standard`
+    - To this line:
+      - `from solcx import compile_standard, install_solc`
+    - And then, we need to add a line right before we run the `compile_standard` code:
+      - `install_solc("0.6.0")`