import re
logdata = r"""159.253.153.40 - - [21/Jun/2019:15:46:10 -0700] "POST /e-business HTTP/1.0" 504 19845
136.195.158.6 - feeney9464 [21/Jun/2019:15:46:11 -0700] "HEAD /open-source/markets HTTP/2.0" 204 21149"""
pattern = r'''
(?P<host>\d+(?:\.\d+){3}) # 1+ digits and 3 occurrenses of . and 3 digits
\s+\S+\s+                 # 1+ whitespaces, 1+ non-whitespaces, 1+ whitespaces
(?P<user_name>\S+)\s+\[   # 1+ non-whitespaces (Group "user_name"), 1+ whitespaces and [
(?P<time>[^\]\[]*)\]\s+   # Group "time": 0+ chars other than [ and ], ], 1+ whitespaces
"(?P<request>[^"]*)"      # ", Group "request": 0+ non-" chars, "
'''
for item in re.finditer(pattern,logdata,re.VERBOSE):
    print(item.groupdict())

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