#nix-lang 

The  `with` function brings all attributes from a given set, e.g nixpkgs, into the local scope. Making them accessible as if they were declared in the same file.

An example, bringing everything from nixpkgs into scope:
```
with import <nixpkgs>;
with python310Packages; <-- declared in nixpkgs

buildPythonPackage <-- declared in python310Packages
```

The import statement is required here because imports a nix expression from another source, in this case nixpkgs.
It is not required at line two, because python310Packages itself is already in the local scope.


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[Nix Manual](https://nixos.org/manual/nix/stable/language/index.html)