Fix mlxtend importing itself during installation

docs/sources/CHANGELOG.md

@@ -21,6 +21,8 @@ The CHANGELOG for the current development version is available at
 
 - Address NumPy deprecations to make mlxtend compatible to NumPy 1.24 
 - Changed the signature of the `LinearRegression` model of sklearn in the test removing the `normalize` parameter as it is deprecated. ([#1036](https://github.com/rasbt/mlxtend/issues/1036))
+- Add `pyproject.toml` to support PEP 518 builds
+- Fixed installation from sdist failing
 
 ##### New Features and Enhancements
 
@@ -951,4 +953,4 @@ imput arrays via `transform` and `fit_transform`
 
 ### Version 0.1.1 (2014-08-13)
 
-- Simplified code for ColumnSelector.
+- Simplified code for ColumnSelector.

setup.py

@@ -4,23 +4,32 @@
 #
 # License: BSD 3 clause
 
-from os.path import dirname, join, realpath
+from os.path import abspath, dirname, join, realpath
 
 from setuptools import find_packages, setup
 
-import mlxtend
-
-VERSION = mlxtend.__version__
 PROJECT_ROOT = dirname(realpath(__file__))
 
+
+def get_version(rel_path):
+    here = abspath(dirname(__file__))
+    with open(join(here, rel_path), "r") as f:
+        for line in f.readlines():
+            if line.startswith("__version__"):
+                delim = '"' if '"' in line else "'"
+                return line.split(delim)[1]
+        else:
+            raise RuntimeError("Unable to find version string.")
+
+
 REQUIREMENTS_FILE = join(PROJECT_ROOT, "requirements.txt")
 
 with open(REQUIREMENTS_FILE) as f:
     install_reqs = f.read().splitlines()
 
 setup(
     name="mlxtend",
-    version=VERSION,
+    version=get_version("mlxtend/__init__.py"),
     description="Machine Learning Library Extensions",
     author="Sebastian Raschka",
     author_email="[email protected]",