Pythonically add header to a csv file

Question

I wrote a Python script merging two csv files, and now I want to add a header to the final csv. I tried following the suggestions reported here and I got the following error

Answer 1

You just add one additional row before you execute the loop. This row contains your CSV file header name.

schema = ['a','b','c','b']
row = 4
generators = ['A','B','C','D']
with open('test.csv','wb') as csvfile:    
     writer = csv.writer(csvfile, delimiter=delimiter)
# Gives the header name row into csv
     writer.writerow([g for g in schema])   
#Data add in csv file       
     for x in xrange(rows):
         writer.writerow([g() for g in generators])