How to read and write to a file in Python?

To read from a file in Python, you would use syntax similar to the following:

```
filename = ‘path_to_your_file/filename.extension’

Opening file for reading
with open(filename, ‘r’) as file: print(file.read()) # Reads the entire content of the file # If the file is too big, you may want to read it line by line for line in file: print(line)
```

Here is how you can write to a file:

```
filename = ‘path_to_your_file/filename.extension’

Opening file for writing
with open(filename, ‘w’) as file: file.write(‘Hello, world!’) # Write a string to the file
```

Note:

1. Write operation ‘w’ overwrites the existing file content. Using ‘a’ mode to append content to an existing file.

1. Always remember to close your files when you’re done with using `with open()` method which automatically takes care of closing.

1. Using `with open()` method is preferred as it effectively handles resource leaks and makes your code cleaner.