import re
prefix_pattern = "PREFIX"
postfix_pattern = "POSTFIX"
shared_pattern = "[a-zA-z]*"
test_pattern ="("+prefix_pattern+shared_pattern+")|("+shared_pattern+postfix_pattern+")$"
pattern = re.compile(test_pattern)
test = 'PREFIXabc123' # Match
#test = 'abcPOSTFIX' # No match
x = re.match(pattern,test)
if x:
print(x.group())
else:
print("Not found")
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