Python start from a specific string line and write?

Python start from a specific string line and write? - Printable Version

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Python start from a specific string line and write? - searching1 - Jun-27-2019

I want to match a specific string and once match start writing the next line after after the matched string.

from output save in x variable I want to match "Current configuration" then write then start writing from next line.

Heres the sample output sting.

show run
Building configuration...

Current configuration : 1505 bytes
!
Content1
Content1
!
Content2
Content2

Once matched write but starting from next line. heres the target output.

!
Content1
Content1
!
Content2
Content2

Sample Configuration(but string the for line and not matching):

str = """show run
Building configuration...

Current configuration : 1505 bytes
!
Content1
Content1
!
Content2
Content2"""

with open('test.txt', 'w') as x:
    print str
    if "Current configuration" in str:
        x.writelines(itertools.islice(str, 4, None))

Thanks

RE: Python start from a specific string line and write? - perfringo - Jun-27-2019

It's never good idea to use built-ins as names in your code:

>>> str(12)
'12'
>>> str = 'something'
>>> str(12)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: 'str' object is not callable

From print statement I assume that Python 2.x is used. Is there any particular reason not to use Python 3?

Unfortunately I don't understand what you want to accomplish so no help here.

EDIT: it's tempting to think that now I understand what should be accomplished.

I see that itertools module is used and there is more suitable function: itertools.dropwhile()

from itertools import dropwhile

s = """show run
Building configuration...
 
Current configuration : 1505 bytes
!
Content1
Content1
!
Content2
Content2"""

iterator = dropwhile(lambda line: not line.startswith('Current'), s.split('\n')) 
next(iterator)
for line in iterator:
    print(line)

Output:!
Content1
Content1
!
Content2
Content2