import csv
crit_sev = "Critical"
high_sev = "High"
med_sev = "Medium"
low_sev = "Low"
reader = csv.reader(open('sample.csv', 'r'))
row=0
my_list = []
for row in reader:
    if row[1] == crit_sev:
        my_list.append(row)
    elif row[1] == high_sev:
        my_list.append(row)
    elif row[1] == med_sev:
        my_list.append(row)
    elif row[1] == low_sev:
        my_list.append(row)

writer = csv.writer(open("sample.csv", 'w'))
header = ['IP Address', 'Severity', 'Score']
writer.writerow([header])
for word in my_list:
    writer.writerow([word])