# uproot.KeyInFileError

Defined in uproot.exceptions on line 16.

Inheritance order:
`builtins.KeyError` `builtins.LookupError` `builtins.Exception` `builtins.BaseException`

class uproot.exceptions.KeyInFileError(key, because='', cycle=None, keys=None, file_path=None, object_path=None)

  Exception raised by attempts to find ROOT objects in `TDirectories` or `TBranches` in uproot.behaviors.TBranch.HasBranches, which both have a Python `Mapping` interface (square bracket syntax to extract items).

  This exception descends from Python’s `KeyError`, so it can be used in the normal way by interfaces that expect a missing item in a `Mapping` to raise `KeyError`, but it provides more information, depending on availability:

  - `because`: an explanatory message

  - `cycle`: the ROOT cycle number requested, if any

  - `keys`: a list or partial list of keys that are in the object, in case of misspelling

  - `file_path`: a path (or URL) to the file

  - `object_path`: a path to the object within the ROOT file.