import re
s = "'didn't'"
print(s.strip("'")[s.strip("'").find("'")+1])
print(re.search(r'\b\'(\w)', s).group(1))
print(re.search(r'\b\'([^\W\d_])', s).group(1))
print(re.search(r'\b\'([a-z])', s, flags=re.I).group(1))
print(re.findall(r'\b\'([a-z])', "'didn't know I'm a student'", flags=re.I))
aW1wb3J0IHJlCgpzID0gIidkaWRuJ3QnIgpwcmludChzLnN0cmlwKCInIilbcy5zdHJpcCgiJyIpLmZpbmQoIiciKSsxXSkKcHJpbnQocmUuc2VhcmNoKHInXGJcJyhcdyknLCBzKS5ncm91cCgxKSkKcHJpbnQocmUuc2VhcmNoKHInXGJcJyhbXlxXXGRfXSknLCBzKS5ncm91cCgxKSkKcHJpbnQocmUuc2VhcmNoKHInXGJcJyhbYS16XSknLCBzLCBmbGFncz1yZS5JKS5ncm91cCgxKSkKcHJpbnQocmUuZmluZGFsbChyJ1xiXCcoW2Etel0pJywgIidkaWRuJ3Qga25vdyBJJ20gYSBzdHVkZW50JyIsIGZsYWdzPXJlLkkpKQ==