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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 notify_slack_channel(self):
 """Post message to a defined Slack channel."""

        message = get_template(template_file='slack/pipeline-prepare-ran.j2', info=self.info)

        if self.settings['pipeline']['notifications']['slack']:
            post_slack_message(
                message=message,
                channel=self.settings['pipeline']['notifications']['slack'],
                username='pipeline-bot',
                icon_emoji=':gear:')