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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 post_card(name,
              message,
              hook_url=None,
              title=None,
              theme_color=None):
    '''
    Send a message to a Microsft Teams channel

    .. code-block:: yaml

        send-msteams-message:
          msteams.post_card:
            - message: 'This state was executed successfully.'
            - hook_url: https://outlook.office.com/webhook/837

    The following parameters are required:

    message
        The message that is to be sent to the MS Teams channel.

    The following parameters are optional:

    hook_url
        The webhook URL given configured in Teams interface,
        if not specified in the configuration options of master or minion.
    title
        The title for the card posted to the channel
    theme_color
        A hex code for the desired highlight color
    '''
    ret = {'name': name,
           'changes': {},
           'result': False,
           'comment': ''}

    if __opts__['test']:
        ret['comment'] = 'The following message is to be sent to Teams: {0}'.format(message)
        ret['result'] = None
        return ret

    if not message:
        ret['comment'] = 'Teams message is missing: {0}'.format(message)
        return ret

    try:
        result = __salt__['msteams.post_card'](
            message=message,
            hook_url=hook_url,
            title=title,
            theme_color=theme_color,
        )
    except SaltInvocationError as sie:
        ret['comment'] = 'Failed to send message ({0}): {1}'.format(sie, name)
    else:
        if isinstance(result, bool) and result:
            ret['result'] = True
            ret['comment'] = 'Sent message: {0}'.format(name)
        else:
            ret['comment'] = 'Failed to send message ({0}): {1}'.format(result['message'], name)

    return ret