import re
p = re.compile(r'^([a-zA-Z0-9]+)(?:\r?\n|\r)Ethernet IP Address: ([\d.]+)(?:\r?\n|\r)Ethernet Subnetmask: ([\d.]+)(?:(?:\r?\n|\r)Host Name: ([a-z\d]+)(?:\r?\n|\r)Gateway IP Address: ([\d.]+))?', re.MULTILINE)
s = "sw1:FID256:root> ipaddrshow \n\nCHASSIS\nEthernet IP Address: 10.17.11.10\nEthernet Subnetmask: 255.255.210.0\n\nCP0\nEthernet IP Address: 10.17.11.11\nEthernet Subnetmask: 255.255.210.0\nHost Name: cp0\nGateway IP Address: 10.17.48.1\n\nCP1\nEthernet IP Address: 10.17.11.12\nEthernet Subnetmask: 255.255.210.0\nHost Name: cp1\nGateway IP Address: 10.17.18.1\n\nsw1:FID256:root>"
result = ["{0},ip {1} {0},mask {2} {3},gw {4}".format(z.group(1).lower(),z.group(2),z.group(3).lower(),z.group(4),z.group(5)) if z.group(4) else "{0},ip {1} {0},mask {2}".format(z.group(1).lower(),z.group(2),z.group(3)) for z in p.finditer(s)]
print(result)

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