[PATCH] deb822: Make Deb822Dict unhashable.

[John Wright]

Mutable containers should generally not be hashable.  Strangely (to me,
at laest), DictMixin inherits the default __hash__ implementation, which
makes Python complain with -3.  This patch explicitly sets __hash__ to
None.

This is one (very small) step toward Python 3 compatibility.
---
 lib/debian/deb822.py |   14 +++++++++-----
 1 files changed, 9 insertions(+), 5 deletions(-)

diff --git a/lib/debian/deb822.py b/lib/debian/deb822.py
index 47c921d..11429cc 100644
--- a/lib/debian/deb822.py
+++ b/lib/debian/deb822.py
@@ -33,7 +33,6 @@ except (ImportError, AttributeError):
     _have_apt_pkg = False
 
 import chardet
-import new
 import re
 import string
 import sys
@@ -130,6 +129,9 @@ class Deb822Dict(object, UserDict.DictMixin):
     in the _parsed dictionary are exposed.
     """
 
+    # Mutable containers should not be hashable.
+    __hash__ = None
+
     # See the end of the file for the definition of _strI
 
     def __init__(self, _dict=None, _parsed=None, _fields=None,
@@ -786,10 +788,12 @@ class PkgRelation(object):
 
         def pp_atomic_dep(dep):
             s = dep['name']
-            if dep.has_key('version') and dep['version'] is not None:
-                s += ' (%s %s)' % dep['version']
-            if dep.has_key('arch') and dep['arch'] is not None:
-                s += ' [%s]' % string.join(map(pp_arch, dep['arch']))
+            version = dep.get('version')
+            arch = dep.get('arch')
+            if version is not None:
+                s += ' (%s %s)' % version
+            if arch is not None:
+                s += ' [%s]' % string.join(map(pp_arch, arch))
             return s
 
         pp_or_dep = lambda deps: string.join(map(pp_atomic_dep, deps), ' | ')
-- 
1.7.4.4