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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:

def netdevs():
    ''' RX and TX bytes for each of the network devices '''

    with open('/proc/net/dev') as f:
        net_dump = f.readlines()
    
    device_data={}
    data = namedtuple('data',['rx','tx'])
    for line in net_dump[2:]:
        line = line.split(':')
        if line[0].strip() != 'lo':
            device_data[line[0].strip()] = data(float(line[1].split()[0])/(1024.0*1024.0), 
                                                float(line[1].split()[8])/(1024.0*1024.0))
    
    return device_data