Installation

Two pieces: the justcatit package from PyPI and an installed .NET runtime.

Prerequisites #

A 64-bit Python, 3.8 or later. The package depends on pythonnet, a compiled extension that is released for a range of Python versions — pip picks the pythonnet release that fits your Python; a Python newer than the latest pythonnet release cannot install the module until pythonnet catches up.

An installed .NET runtime, version 10 or later. The package does not bring its own runtime; pythonnet finds the one installed on the machine (through DOTNET_ROOT or dotnet on PATH) and uses the highest version it finds. Without one, the first function call fails with RuntimeError: Failed to create a .NET runtime (coreclr). On Windows:

winget install Microsoft.DotNet.Runtime.10

or download the .NET Runtime (x64) from https://dotnet.microsoft.com/download/dotnet/10.0. The .NET SDK works too but is not needed.

Windows x64 is the only supported platform — see Platforms. On Linux and macOS, use the PowerShell module or CAT CLI instead.

Some data source providers need additional software installed on the machine. The requirement belongs to the provider, not to the module — each provider page states what it needs, and the Providers overview marks which providers need a driver.

Install #

pip install justcatit

(py -m pip install justcatit on Windows when pip is not on PATH.) The package is large — it carries the CAT engine — so the first install takes a moment. Pin the version in automated processes: pip install justcatit==3.0.0.

Verify the installation #

from justcatit import cat
print(cat.get_instance())

get_instance needs neither a token nor a key; it prints the instance (versions, platform, whether a key is set) and proves the .NET runtime was found.

Update #

pip install --upgrade justcatit

Uninstall #

pip uninstall justcatit

Uninstalling removes the package only. Project files, test definitions and results stay where they are; the license key and instance identity stay in %APPDATA%\CAT\ for the other CAT tools.

Related #

• Introduction — import, session model, sign-in.
• Get started with the Python module — the tutorial.