Update Python Cheat Sheet

Author: codingforentrepreneurs

PythonCheatSheet.md

@@ -194,5 +194,27 @@ print(text)
 
 ```
 
+## Working with Files
+
+```
+file_obj = open(file_name, "<mode>")
+```
+
+| Mode | Description |
+| ------------- |:-------------:|
+| "r" | Read only. Default mode. |
+| "rb" | Read only in binary format |
+| "r+" | Read and write |
+| "rb+" | Read and write in binary format |
+| "w" | Write only. Overwrites existing file or creates a new file. |
+| "wb" | Write only in binary format. Overwrites existing file or creates a new file. |
+| "w+" | Read and write. Overwrites existing file or creates a new file. |
+| "wb+" | Read and write in binary format. Overwrites existing file or creates a new file. |
+| "a" | Append to existing file or creates new file. |
+| "ab" | Append to existing file or creates new file in binary format. |
+| "a+" | Read and append. Overwrites existing file or creates a new file. |
+| "ab+" | Read and append in binary format. Overwrites existing file or creates a new file. |
+
+