import re
email = 'MACHINE: =\nldnmdsbatchxl01\n\n\nMACHINE: p2prog06\n\n\nMACHINE: p1prog=^M\n07'
res = list(set([re.sub(r'=(?:\^M)?|[\r\n]+', '', x) for x in re.findall(r'\bMACHINE:\s*(.*(?:(?:\r\n?|\n)\S+)?)', email, re.M)]))
print(res)
aW1wb3J0IHJlCmVtYWlsID0gJ01BQ0hJTkU6ID1cbmxkbm1kc2JhdGNoeGwwMVxuXG5cbk1BQ0hJTkU6IHAycHJvZzA2XG5cblxuTUFDSElORTogcDFwcm9nPV5NXG4wNycKcmVzID0gbGlzdChzZXQoW3JlLnN1YihyJz0oPzpcXk0pP3xbXHJcbl0rJywgJycsIHgpIGZvciB4IGluIHJlLmZpbmRhbGwocidcYk1BQ0hJTkU6XHMqKC4qKD86KD86XHJcbj98XG4pXFMrKT8pJywgZW1haWwsIHJlLk0pXSkpCnByaW50KHJlcyk=