You can pass ZipFile.open() to pandas.read_csv() to construct a pandas.DataFrame from a csv-file packed into a multi-file zip.
Code:
pd.read_csv(zip_file.open('file3.txt'))
Example to read all .csv into a dict:
from zipfile import ZipFile
zip_file = ZipFile('textfile.zip')
dfs = {text_file.filename: pd.read_csv(zip_file.open(text_file.filename))
for text_file in zip_file.infolist()
if text_file.filename.endswith('.csv')}