Django Admin : Action for Exporting User details to CSV

admin.py

from django.http import HttpResponse, HttpResponseRedirect
from django.contrib import admin
from django.contrib.auth.admin import UserAdmin

def export_to_csv (modeladmin, request, queryset):
    import csv, StringIO
    from django.core.servers.basehttp import FileWrapper
    
    cols = ['username','email','first_name','last_name']

    # get qs values
    data = list( queryset.values_list(*cols) )

    if not data:
        messages.error(request, 'No data to export')
        return HttpResponseRedirect( request.get_full_path() )

    # create empty csv
    csv_file = StringIO.StringIO()
    csv_writer = csv.writer(csv_file, quoting = csv.QUOTE_ALL)

    # add headers
    csv_writer.writerow( cols )

    # add qs values
    for row in data:
    	csv_writer.writerow( [s.encode('utf-8') for s in row] )

    csv_file.flush()
    csv_file.seek(0)

    response = HttpResponse(FileWrapper( csv_file ), content_type='text/csv')
    response['Content-Disposition'] = "attachment; filename=user-csv-export.csv"

    return response

export_to_csv.short_description = "Export to CSV"

class UserProfileAdmin(UserAdmin):
    actions = [ export_to_csv ]
    # ...

You might also what to include the below piece of code inorder for it to work with python3
try:
from StringIO import StringIO
except ImportError:
from io import StringIO

The StringIO and cStringIO modules are gone. Instead, import the io module and use io.StringIO or io.BytesIO for text and data respectively.

Please my exported csv list comes with a 'b' prepended to each value. How can I fix this?? Also how can I get only unique values from db