import re
argStr = '123aBcde'
print('*1*')
print(re.compile(r'.*(?=.*?[a-z])').search(argStr).group())
print(re.compile(r'.*(?=.*[a-z])').search(argStr).group())
#文字列を切り出すため、肯定先読みの表現の前に「.*」を入れています
print('*2*')
print(re.compile(r'(.*?[a-z])').search(argStr).group())
print(re.compile(r'(.*[a-z])').search(argStr).group())
aW1wb3J0IHJlCgphcmdTdHIgPSAnMTIzYUJjZGUnCgpwcmludCgn77yK77yR77yKJykKcHJpbnQocmUuY29tcGlsZShyJy4qKD89Lio/W2Etel0pJykuc2VhcmNoKGFyZ1N0cikuZ3JvdXAoKSkKcHJpbnQocmUuY29tcGlsZShyJy4qKD89LipbYS16XSknKS5zZWFyY2goYXJnU3RyKS5ncm91cCgpKQoj5paH5a2X5YiX44KS5YiH44KK5Ye644GZ44Gf44KB44CB6IKv5a6a5YWI6Kqt44G/44Gu6KGo54++44Gu5YmN44Gr44CMLirjgI3jgpLlhaXjgozjgabjgYTjgb7jgZkKCnByaW50KCfvvIrvvJLvvIonKQpwcmludChyZS5jb21waWxlKHInKC4qP1thLXpdKScpLnNlYXJjaChhcmdTdHIpLmdyb3VwKCkpCnByaW50KHJlLmNvbXBpbGUocicoLipbYS16XSknKS5zZWFyY2goYXJnU3RyKS5ncm91cCgpKQo=