How can I make a for-loop loop through lines instead of characters in a variable?

I have the following code to ssh to a node and find the RSSIs from other devices.

bot_ipv6 is a list of ipv6 addresses to ssh to and the script uses pexpect to ssh.

for address in bot_ipv6:
    session=spawn('ssh -6 root@'+address+'%wlan0')
    #session.logfile = stdout
    session.expect('password:')
    session.sendline("123456")
    session.expect(prompt)
    session.sendline("iwlist wlan0 scan")
    session.expect(prompt)
    data=session.before
    session.close()

data now contains the output of iwlist wlan0 scan at that device.

I want to go through the data and get just the addresses and their corresponding RSSIs. This code works when the command can be ran locally and output to file:

with open("rssi.txt") as fd:
    for line in fd:
        cell_line = match(line,"Cell ")
        if cell_line != None:
            cells.append([])
            line = cell_line[-27:]
        cells[-1].append(line.rstrip())


for cell in cells:
    level.append(matching_line(cell,"Quality=").split()[2].split('=')[1])
    address.append(matching_line(cell,"Address: "))

scanned=dict(zip(address, level))

Where match and matching line are functions defined else where that look in the file for matching characters to what am looking for.

My problem is that I don't know how to output the data to a file but if I try to go through the lineds in the output data as I do when using the file:

for line in data:
        cell_line = match(line,"Cell ")
        if cell_line != None:
            cells.append([])
            line = cell_line[-27:]
        cells[-1].append(line.rstrip())

instead of lines, it loops through each character.

How can I either print the output to a file that I can open locally and scan through as I did before or loop through lines in data instead of single characters?

here is a sample of what data looks like (to get it I put a print data into the script and then just copied it from the output and pasted it here, hopefully no formatting is lost):

iwlist wlan0 scan
wlan0     Scan completed :
          Cell 01 - Address: 02:CA:FF:EE:BA:BE
                    Channel:11
                    Frequency:2.462 GHz (Channel 11)
                    Quality=47/70  Signal level=-63 dBm  
                    Encryption key:off
                    ESSID:"nenenenenene-batman"
                    Bit Rates:1 Mb/s; 2 Mb/s; 5.5 Mb/s; 11 Mb/s; 6 Mb/s
                              9 Mb/s; 12 Mb/s; 18 Mb/s
                    Bit Rates:24 Mb/s; 36 Mb/s; 48 Mb/s; 54 Mb/s
                    Mode:Ad-Hoc
                    Extra:tsf=00000000f8083cfe
                    Extra: Last beacon: 72ms ago
                    IE: Unknown: 00136E656E656E656E656E656E652D6261746D616E
                    IE: Unknown: 010882840B160C121824
                    IE: Unknown: 03010B
                    IE: Unknown: 06020000
                    IE: Unknown: 32043048606C
          Cell 02 - Address: D8:5D:4C:AF:C3:14
                    Channel:11
                    Frequency:2.462 GHz (Channel 11)
                    Quality=21/70  Signal level=-89 dBm  
                    Encryption key:on
                    ESSID:"phome"
                    Bit Rates:1 Mb/s; 2 Mb/s; 5.5 Mb/s; 11 Mb/s; 18 Mb/s
                              24 Mb/s; 36 Mb/s; 54 Mb/s
                    Bit Rates:6 Mb/s; 9 Mb/s; 12 Mb/s; 48 Mb/s
                    Mode:Master
                    Extra:tsf=000000ff16ee018d
                    Extra: Last beacon: 3824ms ago
                    IE: Unknown: 000570686F6D65
                    IE: Unknown: 010882848B962430486C
                    IE: Unknown: 03010B
                    IE: Unknown: 2A0104
                    IE: Unknown: 2F0104
                    IE: Unknown: 32040C121860
                    IE: Unknown: 2D1A7C181BFFFF000000000000000000000000000000000000000000
                    IE: Unknown: 3D160B001700000000000000000000000000000000000000
                    IE: Unknown: DD090010180203F4010000
                    IE: Unknown: DD1E00904C337C181BFFFF000000000000000000000000000000000000000000
                    IE: Unknown: DD1A00904C340B001700000000000000000000000000000000000000

Use str.splitlines to split a string into lines:

for line in data.splitlines():
    # Do things.