__Main__

Question

what does this do
```python
def main():
    pass
if name == "main":
    main()
```
[MOD: added ```python formating -cf]

Steven Parker · Accepted Answer

"Pass" does nothing, so currently the "main" function does not do anything.
Without Markdown formatting (https://teamtreehouse.com/library/previews-and-snapshots), the original syntax is lost, but assuming you meant to test "__name__", that determines if the file is being run by itself instead of being included by another program.

Chris Freeman · Answer

Good question! This is a common python idiom to detect if a module is imported or being executed directly.
When a python module is imported into another module, its __name__ attribute is set to be the same as the module name. When a python module is executed, the top level module attribute __name__ is changed to be "__main__". This way a module can tell the difference between if it is being imported or executed. 
The python idiom 
python
if __name__ == "__main__":
     main()

says, "if my __name__ attribute has been changed to the string "__main__", then execute the function main(). The "pass" would be replaced with the code to be executed.
Post back if you have more questions. Good luck!!

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