enron key compatibility for Python 3

Due to changes in dictionary key order in Python 3, a brief fix has
been created for students using Python 3 over Python 2.

tools/feature_format.py

@@ -48,8 +48,12 @@ def featureFormat( dictionary, features, remove_NaN=True, remove_all_zeroes=True
     return_list = []
 
     if sort_keys:
+        # keys sorted in alphabetical order for final project compatibility
         keys = sorted(dictionary.keys())
     else:
+        # key orders will be different for Python 2 and Python 3; for Python 3
+        # users, load key order from 'python2_datadictkeys.pkl' using pickle to
+        # complete assignments.
         keys = dictionary.keys()
 
     for key in keys:

tools/python2_datadictkeys.pkl

@@ -0,0 +1,294 @@
+(lp0
+S'METTS MARK'
+p1
+aS'BAXTER JOHN C'
+p2
+aS'ELLIOTT STEVEN'
+p3
+aS'CORDES WILLIAM R'
+p4
+aS'HANNON KEVIN P'
+p5
+aS'MORDAUNT KRISTINA M'
+p6
+aS'MEYER ROCKFORD G'
+p7
+aS'MCMAHON JEFFREY'
+p8
+aS'HORTON STANLEY C'
+p9
+aS'PIPER GREGORY F'
+p10
+aS'HUMPHREY GENE E'
+p11
+aS'UMANOFF ADAM S'
+p12
+aS'BLACHMAN JEREMY M'
+p13
+aS'SUNDE MARTIN'
+p14
+aS'GIBBS DANA R'
+p15
+aS'LOWRY CHARLES P'
+p16
+aS'COLWELL WESLEY'
+p17
+aS'MULLER MARK S'
+p18
+aS'JACKSON CHARLENE R'
+p19
+aS'WESTFAHL RICHARD K'
+p20
+aS'WALTERS GARETH W'
+p21
+aS'WALLS JR ROBERT H'
+p22
+aS'KITCHEN LOUISE'
+p23
+aS'CHAN RONNIE'
+p24
+aS'BELFER ROBERT'
+p25
+aS'SHANKMAN JEFFREY A'
+p26
+aS'WODRASKA JOHN'
+p27
+aS'BERGSIEKER RICHARD P'
+p28
+aS'URQUHART JOHN A'
+p29
+aS'BIBI PHILIPPE A'
+p30
+aS'RIEKER PAULA H'
+p31
+aS'WHALEY DAVID A'
+p32
+aS'BECK SALLY W'
+p33
+aS'HAUG DAVID L'
+p34
+aS'ECHOLS JOHN B'
+p35
+aS'MENDELSOHN JOHN'
+p36
+aS'HICKERSON GARY J'
+p37
+aS'CLINE KENNETH W'
+p38
+aS'LEWIS RICHARD'
+p39
+aS'HAYES ROBERT E'
+p40
+aS'MCCARTY DANNY J'
+p41
+aS'KOPPER MICHAEL J'
+p42
+aS'LEFF DANIEL P'
+p43
+aS'LAVORATO JOHN J'
+p44
+aS'BERBERIAN DAVID'
+p45
+aS'DETMERING TIMOTHY J'
+p46
+aS'WAKEHAM JOHN'
+p47
+aS'POWERS WILLIAM'
+p48
+aS'GOLD JOSEPH'
+p49
+aS'BANNANTINE JAMES M'
+p50
+aS'DUNCAN JOHN H'
+p51
+aS'SHAPIRO RICHARD S'
+p52
+aS'SHERRIFF JOHN R'
+p53
+aS'SHELBY REX'
+p54
+aS'LEMAISTRE CHARLES'
+p55
+aS'DEFFNER JOSEPH M'
+p56
+aS'KISHKILL JOSEPH G'
+p57
+aS'WHALLEY LAWRENCE G'
+p58
+aS'MCCONNELL MICHAEL S'
+p59
+aS'PIRO JIM'
+p60
+aS'DELAINEY DAVID W'
+p61
+aS'SULLIVAN-SHAKLOVITZ COLLEEN'
+p62
+aS'WROBEL BRUCE'
+p63
+aS'LINDHOLM TOD A'
+p64
+aS'MEYER JEROME J'
+p65
+aS'LAY KENNETH L'
+p66
+aS'BUTTS ROBERT H'
+p67
+aS'OLSON CINDY K'
+p68
+aS'MCDONALD REBECCA'
+p69
+aS'CUMBERLAND MICHAEL S'
+p70
+aS'GAHN ROBERT S'
+p71
+aS'MCCLELLAN GEORGE'
+p72
+aS'HERMANN ROBERT J'
+p73
+aS'SCRIMSHAW MATTHEW'
+p74
+aS'GATHMANN WILLIAM D'
+p75
+aS'HAEDICKE MARK E'
+p76
+aS'BOWEN JR RAYMOND M'
+p77
+aS'GILLIS JOHN'
+p78
+aS'FITZGERALD JAY L'
+p79
+aS'MORAN MICHAEL P'
+p80
+aS'REDMOND BRIAN L'
+p81
+aS'BAZELIDES PHILIP J'
+p82
+aS'BELDEN TIMOTHY N'
+p83
+aS'DURAN WILLIAM D'
+p84
+aS'THORN TERENCE H'
+p85
+aS'FASTOW ANDREW S'
+p86
+aS'FOY JOE'
+p87
+aS'CALGER CHRISTOPHER F'
+p88
+aS'RICE KENNETH D'
+p89
+aS'KAMINSKI WINCENTY J'
+p90
+aS'LOCKHART EUGENE E'
+p91
+aS'COX DAVID'
+p92
+aS'OVERDYKE JR JERE C'
+p93
+aS'PEREIRA PAULO V. FERRAZ'
+p94
+aS'STABLER FRANK'
+p95
+aS'SKILLING JEFFREY K'
+p96
+aS'BLAKE JR. NORMAN P'
+p97
+aS'SHERRICK JEFFREY B'
+p98
+aS'PRENTICE JAMES'
+p99
+aS'GRAY RODNEY'
+p100
+aS'PICKERING MARK R'
+p101
+aS'THE TRAVEL AGENCY IN THE PARK'
+p102
+aS'NOLES JAMES L'
+p103
+aS'KEAN STEVEN J'
+p104
+aS'TOTAL'
+p105
+aS'FOWLER PEGGY'
+p106
+aS'WASAFF GEORGE'
+p107
+aS'WHITE JR THOMAS E'
+p108
+aS'CHRISTODOULOU DIOMEDES'
+p109
+aS'ALLEN PHILLIP K'
+p110
+aS'SHARP VICTORIA T'
+p111
+aS'JAEDICKE ROBERT'
+p112
+aS'WINOKUR JR. HERBERT S'
+p113
+aS'BROWN MICHAEL'
+p114
+aS'BADUM JAMES P'
+p115
+aS'HUGHES JAMES A'
+p116
+aS'REYNOLDS LAWRENCE'
+p117
+aS'DIMICHELE RICHARD G'
+p118
+aS'BHATNAGAR SANJAY'
+p119
+aS'CARTER REBECCA C'
+p120
+aS'BUCHANAN HAROLD G'
+p121
+aS'YEAP SOON'
+p122
+aS'MURRAY JULIA H'
+p123
+aS'GARLAND C KEVIN'
+p124
+aS'DODSON KEITH'
+p125
+aS'YEAGER F SCOTT'
+p126
+aS'HIRKO JOSEPH'
+p127
+aS'DIETRICH JANET R'
+p128
+aS'DERRICK JR. JAMES V'
+p129
+aS'FREVERT MARK A'
+p130
+aS'PAI LOU L'
+p131
+aS'BAY FRANKLIN R'
+p132
+aS'HAYSLETT RODERICK J'
+p133
+aS'FUGH JOHN L'
+p134
+aS'FALLON JAMES B'
+p135
+aS'KOENIG MARK E'
+p136
+aS'SAVAGE FRANK'
+p137
+aS'IZZO LAWRENCE L'
+p138
+aS'TILNEY ELIZABETH A'
+p139
+aS'MARTIN AMANDA K'
+p140
+aS'BUY RICHARD B'
+p141
+aS'GRAMM WENDY L'
+p142
+aS'CAUSEY RICHARD A'
+p143
+aS'TAYLOR MITCHELL S'
+p144
+aS'DONAHUE JR JEFFREY M'
+p145
+aS'GLISAN JR BEN F'
+p146
+a.