diff --git a/README.md b/README.md
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+# isort Github Action
+
+This action runs isort on a Python repository.
+
+It requires that the [`checkout`][github-checkout] and [`setup-python`][github-setup-python] actions be used first.
+
+## Inputs
+
+### `isortVersion`
+
+Optional. Version of `isort` to use. Defaults to latest version of `isort`.
+
+### `sortPaths`
+
+Optional. List of paths to sort, relative to your project root. Defaults to `.`
+
+### `configuration`
+
+Optional. `isort` configuration options to pass to the `isort` CLI. Defaults to `-check-only --diff`.
+
+### `requirementsFiles`
+
+Optional. Paths to python requirements files to install before running isort.
+If multiple requirements files are provided, they should be separated by a space.
+If custom package installation is required, dependencies should be installed in a separate step before using this action.
+
+## Outputs
+
+### `isort-result`
+
+Output of the `isort` CLI.
+
+## Example usage
+
+```yaml
+name: Run isort
+on:
+  - push
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - uses: actions/setup-python@v2
+        with:
+          python-version: 3.8
+      - uses: jamescurtin/isort-action@master
+        with:
+            requirementsFiles: "requirements.txt requirements-test.txt"
+```
+
+[github-checkout]: https://github.com/actions/checkout
+[github-setup-python]: https://github.com/actions/setup-python
diff --git a/action.yml b/action.yml
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+name: "python-isort"
+author: "jamescurtin"
+description: "Run isort on a Python project"
+
+inputs:
+  isortVersion:
+    description: "Version of isort to use"
+    required: false
+    default: ""
+  sortPaths:
+    description: "files or directories to sort"
+    required: false
+    default: "."
+  configuration:
+    description: "isort configuration options"
+    required: false
+    default: "--check-only --diff"
+  requirementsFiles:
+    description: "path(s) to requirements files that should be installed to properly configure third-party imports"
+    required: false
+    default: ""
+
+outputs:
+  isort-result:
+    description: "isort result"
+    value: ${{ steps.run-isort.outputs.isort-output }}
+
+runs:
+  using: "composite"
+  steps:
+    - run: ${{ github.action_path }}/bin/ensure_python
+      shell: bash
+    - run: ${{ github.action_path }}/bin/install_packages "${{ inputs.isortVersion }}" "${{ inputs.requirementsFiles }}"
+      shell: bash
+    - id: run-isort
+      run: ${{ github.action_path }}/bin/run_isort "${{ inputs.configuration }}" "${{ inputs.sortPaths }}"
+      shell: bash
diff --git a/bin/ensure_python b/bin/ensure_python
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+++ b/bin/ensure_python
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+#!/usr/bin/env bash
+
+# If Python 3 isn't installed, exit
+python3 -V > /dev/null 2>&1 || (echo "python3 is not available. Use the setup-python action" && exit 1)
+
+# Make sure we're using a supported version of Python
+major_version=$(python3 -c 'import sys; print(sys.version_info[0])')
+minor_version=$(python3 -c 'import sys; print(sys.version_info[1])')
+if [ $major_version -lt 3 ] || [ $minor_version -lt 6 ]; then
+    echo "Minimum supported version of python is 3.6, but $(python3 -V) is installed"
+    exit 1
+fi
diff --git a/bin/install_packages b/bin/install_packages
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+++ b/bin/install_packages
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+#!/usr/bin/env bash
+
+isort_version=$1
+requirements_files=$2
+
+if [ -z "$isort_version" ]; then
+    echo "Installing latest version of isort"
+    pip3 install isort[requirements_deprecated_finder,pipfile_deprecated_finder] > /dev/null 2>&1
+else
+    echo "Installing isort==$isort_version"
+    pip3 install isort[requirements_deprecated_finder,pipfile_deprecated_finder]==$isort_version > /dev/null 2>&1
+fi
+
+for file in $requirements_files
+do
+    echo "Running pip install -r $file"
+    pip install -r $file > /dev/null 2>&1
+done
diff --git a/bin/run_isort b/bin/run_isort
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+++ b/bin/run_isort
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+#!/usr/bin/env bash
+
+configuration=$1
+sort_paths=$2
+
+echo "Running isort $configuration $sort_paths"
+isort_result=$(isort $configuration $sort_paths)
+exit_code=$?
+
+echo "::set-output name=isort-output::${isort_result}"
+exit $exit_code