diff --git a/lang/zh/requirements_pypi.txt b/lang/zh/requirements_pypi.txt
new file mode 100644
index 0000000..1a42146
--- /dev/null
+++ b/lang/zh/requirements_pypi.txt
@@ -0,0 +1,13 @@
+numpy>=1.16.2
+scipy>=1.1.0
+matplotlib>=3.0.0
+networkx>=2.2
+scikit-learn>=0.20.0
+tabulate>=0.8.2
+tqdm>=4.26.0
+control>=0.8.2 # for generalized random walk kernels only.
+# slycot>=0.4.0 # for generalized random walk kernels only, which requires a fortran compiler, gfortran for example
+# cvxpy>=1.0.31 # for preimage. Does not work for "pip install graphkit-learn".
+# -e https://files.pythonhosted.org/packages/11/d0/d900870dc2d02ea74961b90c353666c6528a33ea61a10aa59a0d5574ae59/cvxpy-1.0.31.tar.gz # for preimage.
+cvxopt>=1.2.5 # for preimage.
+mosek>=9.2.5; python_version >= '3.6' # for preimage.