Add example script to find components with duplicit contacts

While this script is not terribly useful for day-to-day life, it can
serve as an example on how to use the client.

JIRA: PDC-1105

examples/find-duplicated-contacts.py

@@ -0,0 +1,35 @@
+#! /usr/bin/env python
+# -*- coding: utf-8 -*-
+
+"""
+Find components defining more than one contact with the same role.
+
+In older versions of PDC, it was possible to have multiple contacts with the
+same role. When limits for cardinality of this relationship were introduced, we
+need to find all components that would not pass the new rules.
+
+This script does exactly that. It iterates over all global and release
+components and prints details about any component with duplicate contacts.
+"""
+
+import pdc_client
+
+client = pdc_client.PDCClient('prod')
+
+
+def run(resource):
+    print 'Running tests for {}'.format(resource)
+    for component in pdc_client.get_paged(client[resource]._):
+        pk = component['id']
+        name = component['name']
+        release = component.get('release', {}).get('release_id', '[global]')
+
+        seen_roles = set()
+        for contact in component['contacts']:
+            if contact['contact_role'] in seen_roles:
+                print 'Duplicated roles for {}:{}/{}'.format(pk, release, name)
+            seen_roles.add(contact['contact_role'])
+    print ''
+
+run('global-components')
+run('release-components')