remote python client for podman

* Use podman library for access
* Verbose error checking
* Planned windows and macosx ports

Signed-off-by: Jhon Honce <jhonce@redhat.com>

contrib/python/cmd/lib/future_abstract.py

@@ -0,0 +1,29 @@
+"""Utilities for with-statement contexts.  See PEP 343."""
+
+import abc
+
+import _collections_abc
+
+try:
+    from contextlib import AbstractContextManager
+except ImportError:
+    # Copied from python3.7 library as "backport"
+    class AbstractContextManager(abc.ABC):
+        """An abstract base class for context managers."""
+
+        def __enter__(self):
+            """Return `self` upon entering the runtime context."""
+            return self
+
+        @abc.abstractmethod
+        def __exit__(self, exc_type, exc_value, traceback):
+            """Raise any exception triggered within the runtime context."""
+            return None
+
+        @classmethod
+        def __subclasshook__(cls, C):
+            """Check whether subclass is considered a subclass of this ABC."""
+            if cls is AbstractContextManager:
+                return _collections_abc._check_methods(C, "__enter__",
+                                                       "__exit__")
+            return NotImplemented