1
$ head -n 1 users_y1KGkRi.csv
"email","first_name","last_name","phone_number","address_1","address_2","city","state","zip_code"
$ wc -l users_y1KGkRi.csv
803354 users_y1KGkRi.csv
$ cat users_y1KGkRi.csv | cut -d "," -f 1 | sort | uniq | wc -l
444218
$ head -n 1 restaurants_KmHZSPi.csv
"name","foreign_name","phone_number","commission_rate","address_1","address_2","city","state","zip_code"
$ wc -l restaurants_KmHZSPi.csv
4301 restaurants_KmHZSPi.csv