config system accprofile
    edit "prof_admin"
        set mntgrp read-write
        set admingrp read-write
        set updategrp read-write
        set authgrp read-write
        set sysgrp read-write
        set netgrp read-write
        set loggrp read-write
        set routegrp read-write
        set fwgrp read-write
        set vpngrp read-write
        set utmgrp read-write
        set wanoptgrp read-write
        set endpoint-control-grp read-write
        set wifi read-write
    next
end
config system interface
    edit "port1"
        set vdom "root"
        set ip 192.168.0.150 255.255.255.0
        set allowaccess ping https ssh http telnet
        set type physical
        set role wan
        set snmp-index 1
    next
    edit "port2"
        set vdom "root"
        set type physical
        set role wan
        set snmp-index 2
    next
end

arquivo = "config.txt"
inicio = "config system interface"
fim = "end"
copiar = False
trecho = []

arq = open(arquivo, "r")

for linha in arq :

        if copiar == True:
                trecho.append(linha)

        if inicio in linha:
                copiar = True
                trecho.append(linha)

        if fim in linha:
                copiar = False

arq.close()

for linha in trecho:
        print(linha)

config system interface

    edit "port1"

        set vdom "root"

        set ip 192.168.0.150 255.255.255.0

        set allowaccess ping https ssh http telnet

        set type physical

        set role wan

        set snmp-index 1

    next

    edit "port2"

        set vdom "root"

        set type physical

        set role wan

        set snmp-index 2

    next

end

configuracoes = [] # guarda todos os trechos 'config system interface'
with open('arquivo_de_configuracao.txt') as file:
    dentro_do_bloco = False # verifica se está dentro de um bloco de config desejado
    config = [] # guarda a config atual
    for linha in file: # lê o arquivo linha a linha
        linha = linha.strip('n') # retirar quebra de linha
        if linha == 'config system interface':
            dentro_do_bloco = True # iniciou o bloco
            config.append(linha)
        elif dentro_do_bloco:
            config.append(linha)
            if linha == 'end':
                dentro_do_bloco = False # terminou o bloco
                # junta tudo e guarda na lista de configs encontradas
                configuracoes.append('n'.join(config))
                config = []

# imprime as configurações encontradas
for c in configuracoes:
    print(c)

import re

with open('/tmp/arq.txt') as file:
    conteudo = file.read()
    r = re.compile('^config system interface$(?:(?!^end$).)+^end$', re.MULTILINE | re.DOTALL)
    configuracoes = r.findall(conteudo)

# imprime as configurações encontradas
for c in configuracoes:
    print(c)