Update README.md

Author: alesanchezr

exercises/04-mixed_list/README.md

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+---
+video: "https://www.youtube.com/watch?v=tJ-si9lRkUc"
+---
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 # `04` Mixed List
 
 # 📝instructions:
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 ## 💡 Hint:
 - You can use the `type()` python function.
-- Remember that `len()` return the large of your list.
+- Remember that `len()` return the large of your list.