Avoid errors from setuptools if installed as egg with .pth mapping on subsequent package installs with hostpython

recipes/host_setuptools/__init__.py

@@ -7,7 +7,7 @@ import shutil
 
 
 class HostSetuptools(Recipe):
-    depends = ["hostpython"]
+    depends = ["openssl", "hostpython"]
     archs = ["x86_64"]
     url = "setuptools"
 
@@ -15,5 +15,20 @@ class HostSetuptools(Recipe):
         hostpython = sh.Command(self.ctx.hostpython)
         sh.curl("-O",  "https://bootstrap.pypa.io/ez_setup.py")
         shprint(hostpython, "./ez_setup.py")
+        # Extract setuptools egg and remove .pth files. Otherwise subsequent
+        # python package installations using setuptools will raise exceptions.
+        # Setuptools version 28.3.0
+        site_packages_path = join(
+            self.ctx.dist_dir, 'hostpython',
+            'lib', 'python2.7', 'site-packages')
+        os.chdir(site_packages_path)
+        with open('setuptools.pth', 'r') as f:
+            setuptools_egg_path = f.read().strip('./').strip('\n')
+            unzip = sh.Command('unzip')
+            shprint(unzip, setuptools_egg_path)
+        os.remove(setuptools_egg_path)
+        os.remove('setuptools.pth')
+        os.remove('easy-install.pth')
+        shutil.rmtree('EGG-INFO')
 
 recipe = HostSetuptools()