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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 set_config(name, xpath=None, value=None, commit=False):
    '''
    Sets a Palo Alto XPATH to a specific value. This will always overwrite the existing value, even if it is not
    changed.

    You can add or create a new object at a specified location in the configuration hierarchy. Use the xpath parameter
    to specify the location of the object in the configuration

    name: The name of the module function to execute.

    xpath(str): The XPATH of the configuration API tree to control.

    value(str): The XML value to set. This must be a child to the XPATH.

    commit(bool): If true the firewall will commit the changes, if false do not commit changes.

    SLS Example:

    .. code-block:: yaml

        panos/hostname:
            panos.set_config:
              - xpath: /config/devices/entry[@name='localhost.localdomain']/deviceconfig/system
              - value: <hostname>foobar</hostname>
              - commit: True

    '''
    ret = _default_ret(name)

    result, msg = _set_config(xpath, value)

    ret.update({
        'comment': msg,
        'result': result
    })

    if not result:
        return ret

    if commit is True:
        ret.update({
            'commit': __salt__['panos.commit'](),
            'result': True
        })

    return ret