/// tip

It's easy to activate one virtual environment, get one Python, and then **go to another project**.

And the second project **wouldn't work** because you are using the **incorrect Python**, from a virtual environment for another project.

It's useful being able to check what `python` is being used. 🤓

///

## Why Deactivate a Virtual Environment { #why-deactivate-a-virtual-environment }

    runs-on: ubuntu-latest
    steps:
      - uses: actions/stale@v10
        with:
          operations-per-run: 50
          ascending: true
          exempt-all-milestones: true

          # ISSUES (deactivated) ----------------------------------------------
          # This workflow should touch no issues, so times are set to -1
          # (see actions/stale documentation for the behavior)
          days-before-issue-stale: -1

Make sure you create a [virtual environment](../virtual-environments.md){.internal-link target=_blank}, activate it, and then install it, for example:

```console
$ pip install python-multipart
```

///

## Import `File` and `Form` { #import-file-and-form }

To use `TestClient`, first install <a href="https://www.python-httpx.org" class="external-link" target="_blank">`httpx`</a>.

Make sure you create a [virtual environment](../virtual-environments.md){.internal-link target=_blank}, activate it, and then install it, for example:

```console
$ pip install httpx
```

///

Import `TestClient`.

Create a `TestClient` by passing your **FastAPI** application to it.

Make sure you create a [virtual environment](../virtual-environments.md){.internal-link target=_blank}, activate it, and then install it, for example:

```console
$ pip install python-multipart
```

///

/// note

This is supported since FastAPI version `0.113.0`. 🤓

///

For example, let's say you have 4 API endpoints (*path operations*):

* `/items/public/`
* `/items/private/`
* `/users/{user_id}/activate`
* `/items/pro/`

then you could add different permission requirements for each of them just with dependencies and sub-dependencies:

```mermaid
graph TB

current_user(["current_user"])

## Install dependencies { #install-dependencies }

Make sure you create a [virtual environment](../virtual-environments.md){.internal-link target=_blank}, activate it, and install `jinja2`:

<div class="termy">

```console
$ pip install jinja2

---> 100%
```

</div>

## Using `Jinja2Templates` { #using-jinja2templates }

* Import `Jinja2Templates`.

    </class>
    <class>
      <name>ActivationProperty</name>
      <version>4.0.0+</version>
      <description>This is the property specification used to activate a profile. If the value field
        is empty, then the existence of the named property will activate the profile, otherwise it
        does a case-sensitive match against the property value as well.</description>
      <fields>
        <field>

Make sure you create a [virtual environment](../virtual-environments.md){.internal-link target=_blank}, activate it, and then install it, for example:

```console
$ pip install python-multipart
```

///

## Import `Form` { #import-form }

Import `Form` from `fastapi`:

---

## Install FastAPI { #install-fastapi }

The first step is to install FastAPI.

Make sure you create a [virtual environment](../virtual-environments.md){.internal-link target=_blank}, activate it, and then **install FastAPI**:

<div class="termy">

```console
$ pip install "fastapi[standard]"

---> 100%
```

</div>

/// note