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name: setup-python-env description: > Set up a Python virtual environment and install Reflex. Use when initializing a new Reflex project, setting up a development environment, or when the user needs to create a venv and install dependencies. Load when there is no .venv directory, when the user asks to start a new Reflex app, or when imports fail due to missing packages.

Python Environment Setup for Reflex

This skill handles creating a Python virtual environment and installing Reflex.

Step 1: Check for an existing virtual environment

Look for a .venv directory in the project root:

ls -d .venv 2>/dev/null

If .venv exists, activate it and skip to Step 3.

source .venv/bin/activate

Step 2: Create the virtual environment

If no .venv exists, determine which tools are available.

Option A: uv is available

Check if uv is installed:

uv --version

If uv is found:

1. If no pyproject.toml exists, initialize one:

   uv init --bare
   

2. Create the virtual environment:

   uv venv .venv
   

3. Activate it:

   source .venv/bin/activate
   

Skip to Step 3.

Option B: Fall back to python / pip

If uv is not available, check the Python version:

python3 --version

If the version is older than 3.10, stop and inform the user:

Python 3.10 or newer is required. Please install a more up-to-date version of Python before continuing.

If the version is 3.10 or newer:

1. Create the virtual environment:

   python3 -m venv .venv
   

2. Activate it:

   source .venv/bin/activate
   

3. Upgrade pip:

   pip install --upgrade pip
   

Step 3: Install Reflex

Check if Reflex is already installed:

pip show reflex 2>/dev/null

If Reflex is not installed:

If using uv:

uv add reflex

If using pip:

pip install reflex