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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 send_message(contacts, message):
 """List of contacts the send the message to. You can send messages either to channels and private groups by using the following formats #channel-name @username-direct-message If the channel is the name of a private group / channel, you must first invite the bot to the channel to ensure it is allowed to send messages to the group. Returns true if the message was sent, else `False` Args: contacts (:obj:`list` of `str`,`str`):
 List of contacts message (str):
 Message to send Returns: `bool` """

        if type(contacts) == str:
            contacts = [contacts]

        recipients = list(set(contacts))

        send_notification(
            subsystem='UNKNOWN',
            recipients=[NotificationContact('slack', x) for x in recipients],
            subject=None,
            body_html=message,
            body_text=message
        )