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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 get_free_memory_linux():
 """Return current free memory on the machine for linux. Warning : this script is really not robust Return in MB unit """

    try:
        p = Popen('free -m', shell=True, stdout=PIPE, encoding='utf8')
        stdout_string = p.communicate()[0].split('\n')[2]
    except OSError:
        raise OSError
    stdout_list = stdout_string.split(' ')
    stdout_list = [x for x in stdout_list if x != '']
    return int(stdout_list[3])