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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(string, clean=True):
    '''
    Get an individual DMI string from SMBIOS info

    string
        The string to fetch. DMIdecode supports:
          - ``bios-vendor``
          - ``bios-version``
          - ``bios-release-date``
          - ``system-manufacturer``
          - ``system-product-name``
          - ``system-version``
          - ``system-serial-number``
          - ``system-uuid``
          - ``baseboard-manufacturer``
          - ``baseboard-product-name``
          - ``baseboard-version``
          - ``baseboard-serial-number``
          - ``baseboard-asset-tag``
          - ``chassis-manufacturer``
          - ``chassis-type``
          - ``chassis-version``
          - ``chassis-serial-number``
          - ``chassis-asset-tag``
          - ``processor-family``
          - ``processor-manufacturer``
          - ``processor-version``
          - ``processor-frequency``

    clean
      | Don't return well-known false information
      | (invalid UUID's, serial 000000000's, etcetera)
      | Defaults to ``True``

    CLI Example:

    .. code-block:: bash

        salt '*' smbios.get system-uuid clean=False
    '''

    val = _dmidecoder('-s {0}'.format(string)).strip()

    # Cleanup possible comments in strings.
    val = '\n'.join([v for v in val.split('\n') if not v.startswith('#')])
    if val.startswith('/dev/mem') or clean and not _dmi_isclean(string, val):
        val = None

    return val