当我从Python将数据导出到csv时，该文件为空白。 当我使用打印功能查看数据时，将返回第一个字符串

Question

I am very new to python. I am looking to import data from a .csv into python, use the fields as a variable so that I can string together the inbound data with machine language codes and then export the completed string to a .txt file.

I have the import.csv code working and have defined my variables into python and when I print the results I can see the first line as I need it to output to the .txt file. The issue that I am having is that in trying multiple different write statements, my file is either blank or I get errors.

import csv

with open('july 19.csv',mode='r') as csv_file:
    reader = csv.DictReader(csv_file)
    for records in reader:
            EIN = records['EIN']
            DATE = records['Date Established']
            DUNS = records['DUNS #']
            COMPANYNAME = records['Company Name']
            lineout =('<S>'+ EIN+'$EIN '+EIN+'*'+DATE+')'+COMPANYNAME+'#D-U-N-S '+DUNS)
with open('test2.csv','w') as csvfile:
        fieldnames = ['EIN','Date Established','DUNS #','Company Name']
        writer = csv.DictWriter(csvfile, fieldnames=fieldnames)
        writer.writerows({'EIN' : lineout})

  File "C:/Users/sstibal/PycharmProjects/Training/venv/Training.py", line 14, in <module>
    writer.writerows({'EIN' : lineout})
  File "C:\Users\sstibal\AppData\Local\Programs\Python\Python37-32\lib\csv.py", line 158, in writerows
    return self.writer.writerows(map(self._dict_to_list, rowdicts))
  File "C:\Users\sstibal\AppData\Local\Programs\Python\Python37-32\lib\csv.py", line 148, in _dict_to_list
    wrong_fields = rowdict.keys() - self.fieldnames
AttributeError: 'str' object has no attribute 'keys'

Answer 1

You're missing the fieldnames parameter on writer = csv.DictWriter(f, fieldnames)

The fieldnames parameter is a sequence of keys that identify the order in which values in the dictionary passed to the writerow() method are written to file f.

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