import re
s = '''
id : 1234567890
1)client_name : Abcd
2)family_name : Efgh
5)phon_number : 9876543210
6)address : street number
data : [42|63] [42|62]
id : 14785236984
1)client_name : Abcd
2)family_name : Efgh
5)phon_number : 987555555555
6)address : street number
data : [44|67] [21|1024]
id : 987456321
1)client_name : Abcd
2)family_name : Efgh
5)phon_number : 98744444444
6)address : street number
data : [26|1089] [21|1524]'''
l = re.split(r'\n+(?=\s*id\b)', s.strip(), flags=re.M)
print l
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