SDK - Fixed string comparisons (#1756)

sdk/python/kfp/compiler/_component_builder.py

@@ -128,18 +128,18 @@ def _generate_dockerfile(filename, base_image, entrypoint_filename, python_versi
     raise ValueError('python_version has to be either python2 or python3')
   with open(filename, 'w') as f:
     f.write('FROM ' + base_image + '\n')
-    if python_version is 'python3':
+    if python_version == 'python3':
       f.write('RUN apt-get update -y && apt-get install --no-install-recommends -y -q python3 python3-pip python3-setuptools\n')
     else:
       f.write('RUN apt-get update -y && apt-get install --no-install-recommends -y -q python python-pip python-setuptools\n')
     if requirement_filename is not None:
       f.write('ADD ' + requirement_filename + ' /ml/requirements.txt\n')
-      if python_version is 'python3':
+      if python_version == 'python3':
         f.write('RUN pip3 install -r /ml/requirements.txt\n')
       else:
         f.write('RUN pip install -r /ml/requirements.txt\n')
     f.write('ADD ' + entrypoint_filename + ' /ml/main.py\n')
-    if python_version is 'python3':
+    if python_version == 'python3':
       f.write('ENTRYPOINT ["python3", "-u", "/ml/main.py"]')
     else:
       f.write('ENTRYPOINT ["python", "-u", "/ml/main.py"]')