def memory():
    """Determine the machine's memory specifications.

    Returns
    -------
    mem_info : dictonary
        Holds the current values for the total, free and used memory of the system.

    """

    mem_info = {}

    if platform.linux_distribution()[0]:
        with open('/proc/meminfo') as file:
            c = 0
            for line in file:
                lst = line.split()
                if str(lst[0]) == 'MemTotal:':
                    mem_info['total'] = int(lst[1])
                elif str(lst[0]) in ('MemFree:', 'Buffers:', 'Cached:'):
                    c += int(lst[1])
            mem_info['free'] = c
            mem_info['used'] = (mem_info['total']) - c
    elif platform.mac_ver()[0]:
        ps = subprocess.Popen(['ps', '-caxm', '-orss,comm'], stdout=subprocess.PIPE).communicate()[0]
        vm = subprocess.Popen(['vm_stat'], stdout=subprocess.PIPE).communicate()[0]

        # Iterate processes
        process_lines = ps.split('\n')
        sep = re.compile('[\s]+')
        rss_total = 0  # kB
        for row in range(1, len(process_lines)):
            row_text = process_lines[row].strip()
            row_elements = sep.split(row_text)
            try:
                rss = float(row_elements[0]) * 1024
            except:
                rss = 0  # ignore...
            rss_total += rss

        # Process vm_stat
        vm_lines = vm.split('\n')
        sep = re.compile(':[\s]+')
        vm_stats = {}
        for row in range(1, len(vm_lines) - 2):
            row_text = vm_lines[row].strip()
            row_elements = sep.split(row_text)
            vm_stats[(row_elements[0])] = int(row_elements[1].strip('\.')) * 4096

        mem_info['total'] = rss_total
        mem_info['used'] = vm_stats["Pages active"]
        mem_info['free'] = vm_stats["Pages free"]
    else:
        raise('Unsupported Operating System.\n')
        exit(1)

    return mem_info
Determine the machine's memory specifications.

    Returns
    -------
    mem_info : dictonary
        Holds the current values for the total, free and used memory of the system.