# Writing traversals to a file in python3.x issue

I am trying to traverse a heap, and write the traversal to a file but I am failing miserably.

I keep getting an issue with the maximum traversal depth that spams my terminal when all I want is for the node to be printed out in the file.

Asked by:

**Aida535**| Posted: 06-12-2021

# Answer 1

I think your code should look more like this:

```
def inorder(self, file):
if self._left is not None:
file.write(str(self) + ' ')
self._left.inorder(file)
file.write(str(self) + ' ')
if self._right is not None:
file.write(str(self) + ' ')
self._right.inorder(file)
```

Note that:

- The
`file`

to write to is an argument, passed to the recursive calls, not`open`

ed each time; - Testing for
`None`

by identity not equality; and - I am assuming that you have a tree structure where
`self._left`

and`self._right`

are instances of the same class as`self`

(as you've provided so little of the class, it's hard to be sure, but`self.inorder(self._left)`

makes no sense).

When you call this, on some instance `instance`

of your class, it would look like:

```
with open(...) as f:
instance.inorder(f)
```

Answered by: **Patrick310**| Posted: 07-01-2022

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