How to create and manage Python environments in Visual Studio
A Python environment is a context in which you run Python code and includes global, virtual, and conda environments. An environment consists of an interpreter, a library (typically the Python Standard Library), and a set of installed packages. These components together determine which language constructs and syntax are valid, what operating-system functionality you can access, and which packages you can use.
In Visual Studio on Windows, the Python Environments window, as described in this article, is where you manage these environments and select one as the default for new projects. For any given project, you can also select a specific environment rather than use the default.
If you're new to Python in Visual Studio, see the following articles for necessary background:
Also note that you cannot manage environments for Python code that is opened only as a folder using the File > Open > Folder command. Instead, Create a Python project from existing code to enjoy the environment features of Visual Studio.
If you want to install packages in an environment, refer to the Packages tab reference.
Types of environments
Each Python installation (for example, Python 2.7, Python 3.6, Python 3.7, Anaconda 4.4.0, etc., see Install Python interpreters) maintains its own global environment. Each environment is composed of the specific Python interpreter, its standard library, and a set of pre-installed packages. Installing a package into a global environment makes it available to all projects using that environment. If the environment is located in a protect area of the file system (within c:\program files, for example), then installing packages requires administrator privileges.
Global environments are available to all projects on the computer. In Visual Studio, you select one global environment as the default, which is used for all projects unless you specifically choose a different one for a project. For more information, see Select an environment for a project.
Because packages installed into a global environment are available to all projects that use that environment, conflicts may occur when two projects require incompatible packages or different versions of the same package. Virtual environments avoid such conflicts by using the interpreter and standard library from a global environment but maintaining their own package stores in isolated folders.
In Visual Studio, you can create a virtual environment for a specific project, which is stored in a subfolder in the project. Visual Studio provides a command to generate a requirements.txt file from the virtual environment, making it easy to recreate the environment on other computers. For more information, see Use virtual environments.
A conda environment is one created using the
conda tool, or with integrated conda management in Visual Studio 2017 version 15.7 and higher. (Requires Anaconda or Miniconda; Anaconda is available through the Visual Studio installer, see Installation - Visual Studio 2017.)
For best results with conda environments, use conda 4.4.8 or later (conda versions are different from Anaconda versions). Install Anaconda 5.1 from the Visual Studio 2017 installer.
To see the conda version, where conda environments are stored, and other information, run
conda info at an Anaconda command prompt (that is, a command prompt where Anaconda is in the path):
Your conda environment folders appear as follows:
envs directories : c:\anaconda3\envs C:\Users\user\AppData\Local\conda\conda\envs C:\Users\user\.conda\envs
Because conda environments are not stored with a project, they act similarly to global environments. For example, installing a new package into a conda environment makes that package available to all projects using that environment.
For Visual Studio 2017 version 15.6 and earlier, you can use conda environments by pointing to them manually as described under Manually identify an existing environment.
Visual Studio 2017 version 15.7 and later detects conda environments automatically and displays them in the Python Environments window as described in the next section.
The Python Environments window
The screenshots shown in this section represent Visual Studio 15.8. You may see different UI depending on your version of Visual Studio.
The environments that Visual Studio knows about are displayed in the Python Environments window. To open the window, use one of the following methods:
- Select the View > Other Windows > Python Environments menu command.
Right-click the Python Environments node for a project in Solution Explorer and select View All Python Environments:
In either case, the Python Environments window appears as a sibling tab to Solution Explorer:
Selecting an environment in the list displays various properties and commands for that environment on the Overview tab. For example, you can see in the image above that the interpreter's location is C:\Python36-32. Use the drop-down list below the list of environments to switch to different tabs such as Packages, and IntelliSense. These tabs are described in Python Environments window tab reference.
Selecting an environment does not activate it in any way. The default environment, shown in boldface in the list, is the currently activated environment that Visual Studio uses for any new projects. To activate a different environment, use the Make this the default environment for new projects command. Within the context of a project you can always activate a different environment. For more information, see Select an environment for a project.
To the right of each listed environment is a control that opens an Interactive window for that environment. (In Visual Studio 2017 15.5 and earlier, another control appears that refreshes the IntelliSense database for that environment. See Environments window tab reference for details about the database.)
When you expand the Python Environments window wide enough, you get a fuller view of your environments that you may find more convenient to work with.
Although Visual Studio respects the system-site-packages option, it doesn't provide a way to change it from within Visual Studio.
|Watch a video (Microsoft Virtual Academy) on Python environments in Visual Studio (2m 35s).|
What if no environments appear?
If no environments appear, it means Visual Studio failed to detect any Python installations in standard locations. For example, you may have installed Visual Studio 2017 but cleared all the interpreter options in the installer options for the Python workload. Similarly, you may have installed Visual Studio 2015 or earlier but did not install an interpreter manually (see Install Python interpreters).
If you know you have a Python interpreter on your computer but Visual Studio (any version) did not detect it, then use the + Custom command to specify its location manually. See the next section, Manually identify an existing environment.
Visual Studio detects updates to an existing interpreter, such as upgrading Python 2.7.11 to 2.7.14 using the installers from python.org. During the installation process, the older environment disappears from the Python Environments list before the update appears in its place.
However, if you manually move an interpreter and its environment using the file system, Visual Studio won't know the new location. For more information, see Move an interpreter.
Fix or delete invalid environments
If Visual Studio finds registry entries for an environment, but the path to the interpreter is invalid, then the Python Environments window shows the name with a strikeout font:
To correct an environment you wish to keep, first try using its installer's Repair process. The installers for standard Python 3.x, for example, include that option.
To correct an environment that doesn't have a repair option, or to remove an invalid environment, use the following steps to modify the registry directly. Visual Studio automatically updates the Python Environments window when you make changes to the registry.
- Run regedit.exe.
- Navigate to HKEY_LOCAL_MACHINE\SOFTWARE\Python for 32-bit interpreters, or HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Python for 64-bit interpreters. For IronPython, look for IronPython instead.
- Expand the node that matches the distribution, such as PythonCore for CPython or ContinuumAnalytics for Anaconda. For IronPython, expand the version number node.
Inspect the values under the InstallPath node:
- If the environment still exists on your computer, change the value of ExecutablePath to the correct location. Also correct the (Default) and WindowedExecutablePath values as necessary.
- If the environment no longer exists on your computer and you want to remove it from the Python Environments window, delete the parent node of InstallPath, such as 3.6 in the image above.
Manually identify an existing environment
Use the following steps to identify an environment that's installed in a non-standard location (including conda environments in Visual Studio 2017 version 15.6 and earlier):
Select + Custom in the Python Environments window, which opens the Configure tab:
Enter a name for the environment in the Description field.
Enter or browse (using ...) to the path of the interpreter in the Prefix path field.
If Visual Studio detects a Python interpreter at that location (such as the path shown below for a conda environment), it enables the Auto Detect command. Selecting Auto Detect completes the remaining fields. You can also complete those fields manually.
Once the fields contain the values you want, select Apply to save the configuration. You can now use the environment like any other within Visual Studio.
If you need to remove a manually identified environment, select the Remove command on the Configure tab. Auto-detected environments do not provide this option. For more information, see Configure tab.
Create a conda environment
Visual Studio 2017 version 15.7 and later.
Select + Create conda environment in the Python Environments window, which opens a Create new conda environment tab:
Enter a name for the environment in the Name field, select a base Python interpreter in the Python field, and select Create.
The Output window shows progress for the new environment, with a few CLI instructions once creation is complete:
Within Visual Studio, you can activate a conda environment for a project as you would any other environment as described on Select an environment for a project.
To install packages in the environment, use the Packages tab.