FileLineFilter, file read, file write, with

from __future__ import print_function      #Compatibilidade func print python 2/3
from os.path import isfile

def FileLineFilter(StrFilter, FileIn, FileOut):
    #Remover as linhas que iniciem ou teminem com determinada expressão
    with open(FileIn, 'r') as inf, open(FileOut, 'w') as ouf:
        for LineStr in inf:
            if (not LineStr.startswith(StrFilter)) and (not LineStr.endswith(StrFilter + '\n')):
                ouf.write(LineStr)
    #python close files here

#File names and filter
StrFilter = '#'
FileIn = 'FileNameIN.txt'
FileOut = 'FileNameOut.txt'

#Validate files
assert isfile(FileIn), 'Arquivo de entrada (%s) nao existe. Verifique.' %(FileIn)
assert not isfile(FileOut), 'Arquivo de saida (%s) ja existe. Verifique.' %(FileOut)

FileLineFilter(StrFilter, FileIn, FileOut)
with open(FileOut, 'r') as f:
    print(f.read())