Learn

To begin, let’s define our depth-first search function signature. We’ll start by writing a simple function to check if a provided tree node matches a given target value. If we have a match, then we return the node.

### Instructions

**1.**

Within **dfs.py**, under the `print()`

statement, define a new function `dfs()`

which accepts two parameters:

- the root node, let’s call it
`root`

- the value we’re searching for, let’s call it
`target`

Start by having the new function simply return `None`

.

**2.**

Now let’s modify our function to check if the provided root node matches our target value. If we have a match, then we should return the root node.

Before you return `None`

, create an `if`

statement that checks whether `root.value`

is equal to `target`

. Inside the indented `if`

block, return the `root`

object.

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