Python for each row, while column A value is the same, add to list. When column A value changes, separate list

Question

I'm trying to assess a CSV/Excel file that is organized like this:

172 Afghanistan AFG 1961    0
173 Afghanistan AFG 1962    0
174 Afghanistan AFG 1963    0
175 Afghanistan AFG 1964    0
176 Afghanistan AFG 1965    0
177 Afghanistan AFG 1966    0
178 Afghanistan AFG 1967    0
179 Afghanistan AFG 1968    0
180 Afghanistan AFG 1969    0
181 Afghanistan AFG 1970    0
182 Afghanistan AFG 1971    0
183 Afghanistan AFG 1972    0
184 Afghanistan AFG 1973    1
185 Afghanistan AFG 1974    0
186 Afghanistan AFG 1975    0
187 Afghanistan AFG 1976    3
188 Afghanistan AFG 1977    0
189 Afghanistan AFG 1978    0
190 Afghanistan AFG 1979    0
191 Afghanistan AFG 1980    0
192 Afghanistan AFG 1981    0
193 Afghanistan AFG 1982    0
194 Afghanistan AFG 1983    0
195 Afghanistan AFG 1984    0
196 Afghanistan AFG 1985    0
197 Afghanistan AFG 1986    0
198 Afghanistan AFG 1987    0
199 Afghanistan AFG 1988    0
200 Afghanistan AFG 1989    0
279 Albania     ALB 1961    0
280 Albania     ALB 1962    0
281 Albania     ALB 1963    0
282 Albania     ALB 1964    2

Essentially, I'm trying to put the 2nd column (country names) in one list with no repeats (country_names = ['Afghanistan', 'Albania',…]), and another list of lists of the last column into a list like this: list_of_regime_lists=[[0,0,0,0,0,0,0,…],[0,0,0,0,0,0,0,…], etc.]

Is there a way to write a line of code WITHOUT USING NUMPY OR PANDAS along the lines of "while column remains same value, append line[4] to list?"

Here's what I have so far:

def read_file(fp):

reader = csv.reader(fp)
next(reader, None)

country_names = []
regime_list = [] 
list_of_regime_lists = []

for line in reader:
    country = line[1]
    regime = int(line[4])
    
    if country != "": 
        if country not in country_names: 
            if regime_list != []:
                list_of_regime_lists.append(regime_list) 
            regime_list = []  
            country_names.append(country)
            regime_list.append(regime)
            if country in country_names:
                regime_list.append(regime)
                
return country_names, list_of_regime_lists

Answer 1

Thanks to @ekhumoro

def read_file(fp):

reader = csv.reader(fp)
next(reader, None)

country_names = []
regime_list = [] 
list_of_regime_lists = []

for line in reader:
    country = line[1]
    regime = int(line[4])
    
    if country != "": 
        if country not in country_names: 
            regime_list = [] 
            list_of_regime_lists.append(regime_list) 
            country_names.append(country)
        regime_list.append(regime)
        if country in country_names:
            regime_list.append(regime)
                
return country_names, list_of_regime_lists