d = { 'foo' : 'bar',
'ev123' : 'found it!',
'baz' : 'qux' }
result = next(v for k, v in d.iteritems() if k.startswith('ev'))
print result
ZCA9IHsgJ2ZvbycgOiAnYmFyJywKICAgICAgJ2V2MTIzJyA6ICdmb3VuZCBpdCEnLAogICAgICAnYmF6JyA6ICdxdXgnIH0KICAgICAgCnJlc3VsdCA9IG5leHQodiBmb3IgaywgdiBpbiBkLml0ZXJpdGVtcygpIGlmIGsuc3RhcnRzd2l0aCgnZXYnKSkKCnByaW50IHJlc3VsdA==