---
id: 6a0dcc730cb92a616f86f0bf
title: "Challenge 295: Schema Validator Part 1"
challengeType: 29
dashedName: challenge-295
---

# --description--

Given an object (JavaScript) or dictionary (Python), determine if it matches the following schema:

```json
{
  username: string
}
```

- Extra keys are allowed

# --hints--

`is_valid_schema({"username": "bob"})` should return `True`.

```js
({test: () => { runPython(`
from unittest import TestCase
TestCase().assertIs(is_valid_schema({"username": "bob"}), True)`)
}})
```

`is_valid_schema({"username": "jen", "posts": 30})` should return `True`.

```js
({test: () => { runPython(`
from unittest import TestCase
TestCase().assertIs(is_valid_schema({"username": "jen", "posts": 30}), True)`)
}})
```

`is_valid_schema({"username": ""})` should return `True`.

```js
({test: () => { runPython(`
from unittest import TestCase
TestCase().assertIs(is_valid_schema({"username": ""}), True)`)
}})
```

`is_valid_schema({"username": 7})` should return `False`.

```js
({test: () => { runPython(`
from unittest import TestCase
TestCase().assertIs(is_valid_schema({"username": 7}), False)`)
}})
```

`is_valid_schema({"posts": 25})` should return `False`.

```js
({test: () => { runPython(`
from unittest import TestCase
TestCase().assertIs(is_valid_schema({"posts": 25}), False)`)
}})
```

# --seed--

## --seed-contents--

```py
def is_valid_schema(obj):

    return obj
```

# --solutions--

```py
def is_valid_schema(obj):
    return isinstance(obj.get("username"), str)
```