import re
 
string = """
msg=audit(1234902.147:88): pid=254 uid=1000 auid=1000 ses=3 subj=random_ex:random_ex:random_ex:d3-d3:w0.c12    30 msg='op=PAM:accounting grantors=pam_unix,pam_localuser acct="lemoney" exe="/usr/bin/grep" hostname=? a    ddr=? terminal=/dev/pts/0 res=success'
 
msg=audit(432787023.324:77): pid=1254 uid=1000 auid=1000 ses=3 subj=random_ex:random_ex:random_ex:d3-d3:w0.c12    30 msg='op=PAM:accounting grantors=pam_unix,pam_localuser acct="lemoney" exe="/usr/bin/tail" hostname=? a    ddr=? terminal=/dev/pts/0 res=success'
"""
 
# lines regex
entries = re.compile(r'^msg=.+', re.MULTILINE)
 
# outer regex
rx = re.compile("""
    ((\w+)='([^']+)') # longer group
    |             # or
    (\w+=\S+)     # single items
    """, re.VERBOSE)
 
# inner regex
ry = re.compile("(\w+)=(\S+)")
 
for entry in entries.finditer(string):
  result = dict()
  for match in rx.finditer(entry.group(0)):
    try:
      key, value = match.group(4).split('=')
      result[key] = value
    except:
      #key = match.group(2)
 
      inner = dict()
      for m in ry.finditer(match.group(3)):
        inner[m.group(1)] = m.group(2)
 
      result["mess"] = inner
 
  print(result)

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