diff --git a/pyproject.toml b/pyproject.toml
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index 0000000..555a914
--- /dev/null
+++ b/pyproject.toml
@@ -0,0 +1,27 @@
+[project]
+name = "qha"
+version = "1.1.0"
+description = "A powerful tool for quasi-harmonic approximation"
+authors = [
+    {name = "Qi Zhang", email = "singularitti@outlook.com"},
+]
+dependencies = [
+    "lazy-property>=0.0.1",
+    "mpmath>=1.3.0",
+    "pandas>=2.1.4",
+    "scientific-string>=0.1.0",
+    "scipy>=1.11.4",
+    "text-stream>=0.2.0",
+    "pyyaml>=6.0.1",
+    "matplotlib>=3.8.2",
+]
+requires-python = ">=3.11"
+readme = "README.md"
+license = {text = "GNU General Public License 3"}
+
+[build-system]
+requires = ["pdm-backend"]
+build-backend = "pdm.backend"
+
+[tool.pdm]
+package-type = "library"
diff --git a/qha/tests/__init__.py b/qha/tests/__init__.py
deleted file mode 100644
index e8eb7d2..0000000
--- a/qha/tests/__init__.py
+++ /dev/null
@@ -1,2 +0,0 @@
-#!/usr/bin/env python3
-# Created at Mar 19, 2018, by Qi Zhang
diff --git a/qha/__init__.py b/src/qha/__init__.py
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diff --git a/qha/fitting.py b/src/qha/fitting.py
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diff --git a/qha/grid_interpolation.py b/src/qha/grid_interpolation.py
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diff --git a/qha/multi_configurations/same_phonon_dos.py b/src/qha/multi_configurations/same_phonon_dos.py
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diff --git a/qha/statmech.py b/src/qha/statmech.py
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diff --git a/qha/thermodynamics.py b/src/qha/thermodynamics.py
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diff --git a/qha/type_aliases.py b/src/qha/type_aliases.py
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diff --git a/qha/v2p.py b/src/qha/v2p.py
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diff --git a/tests/__init__.py b/tests/__init__.py
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