python - Join Multiple Files Dictionary -

i have master table contains fields. want join bunch of other csvs.

current data looks like:

file 1:

key  attrib1  attrib2  attrib3  attrib4 

file 2:

key attrib5 

file 3:

key attrib6 

i want final output like:

key   attrib1  attrib2  attrib3  attrib4 attrib5 attrib6, etc. 

not files contain of keys.

current code:

master = "in.csv" file1 = "file.csv" file2 = "file2.csv" prime = list() d1 = {}  open(master) f:     k in csv.reader(f):         prime.append(k[0])  k in prime:     open(file1,'r') csvfile:         rd = csv.reader(csvfile,delimiter=",")         row in rd:             if row[0] ==k:                 d1 = dict((row[0],row[1]) rows in rd)     open(file2,'r') csvfile:         rd = csv.reader(csvfile,delimiter=",")         row in rd:             if row[0] ==k:                 d1 = d1+dict((row[0],row[1]) rows in rd) 

i think close if not want:

master = "in.csv" filelist = "file.csv", "file2.csv" joined = "joined.csv" dict1 = {}  open(master, 'r') csvfile:     row in csv.reader(csvfile):         key = row[0]         dict1[key] = row[1:]  # note not check duplicate keys  filename in filelist:     open(filename, 'rb') csvfile:         seen = set()         row in csv.reader(csvfile):             key = row[0]             if key in dict1:                 if key in seen:                     print('error: duplicate key %r in file %r - ignored' %                                    (key, filename))                 else:                     dict1[key].append(row[1])                     seen.add(key)             else:  # key not in master                 pass  # ignore              # add null entry keys not present in file         key in dict1:             if key not in seen:                 dict1[key].append(none)  # write data in merged dictionary new csv file open(joined, 'wb') newcsvfile:     csv.writer(newcsvfile).writerows(         ([key]+attrlist) key, attrlist in sorted(dict1.iteritems()))