import re
s = '\r \n \r \n Supersedes\r \n None\r \n \r \n Triax PFG Interface Boards: Inova: P/N 01-903510-02 and Unity plus: P/N 01-903510-03\r \n \r \n Service Serial Numbers:\r \n US00000000-US99999999\r \n \r \n '
print ( re .findall ( r'Supersedes:?\s +[\w -]+\s +(.*)\s Serial Number' , s, re .S ) )
m = re .search ( r'Supersedes:?\s +[\w -]+\s +(.*)\s Serial Number' , s, re .S )
if m:
print ( m.group ( 1 ) )
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