python csv writing SET values - csv

Question

Python 3.6
I am trying to write set values to CSV , I am getting the following output for the given code.
import csv
class test_write:
#classmethod
def test_write1(cls):
fieldnames1 = ['first_name', 'last_name']
cls.write_a_test1(fieldnames=fieldnames1)
#classmethod
def write_a_test1(cls, fieldnames):
with open('/Users/Desktop/delete1.csv', 'w') as csvfile:
writer = csv.DictWriter(csvfile, fieldnames=fieldnames)
writer.writeheader()
abc = cls.var1()
writer.writerow(abc)
print("Done writing")
#staticmethod
def var1():
d = ('my', 'name', 'is', 'hahaha')
c = set()
abc = {'first_name': c, 'last_name': d}
return abc
test_write.test_write1()
When I open CSV file:
Output:
first_name last_name
set() ('my', 'name', 'is', 'hahaha')
I don't want it to print set() in the file if it is empty. Instead I need blank. Variable 'C' might have or might not have values it depends. How do I proceed with that.

Answer 1

Dictwriter expects the keys and values to be strings, so str is being called on the objects. What you should use is something like:
d = ('my', 'name', 'is', 'hahaha')
c = set()
abc = {'first_name': ' '.join(c), 'last_name': ' '.join(d)}
return abc
The the result of the file will be:
first_name,last_name
,my name is hahaha