Why do people write the #!/usr/bin/env python shebang on the first line of a Python script?

Question

It seems to me like the files run the same without that line.

Answer 1

This shebang line allows people to run the script without prepending the Python executable. For example, you can run "./myprogram.py" instead of "python3 ./myprogram.py".

The "/usr/bin/env python" causes the running user's default Python installation to run the program. In some uncommon situations, you might find something like this "#!/local/bin/python2.7" on a real world system where a very specific Python installation is required. It's definitely not ideal, but you can point to a specific Python installation, as opposed to the user's default Python installation, by using a modified shebang line.