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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 add_contacts( self, contacts: List["pyrogram.InputPhoneContact"] ):
 """Use this method to add contacts to your Telegram address book. Args: contacts (List of :obj:`InputPhoneContact <pyrogram.InputPhoneContact>`):
 The contact list to be added Returns: On success, the added contacts are returned. Raises: :class:`RPCError <pyrogram.RPCError>` in case of a Telegram RPC error. """

        imported_contacts = self.send(
            functions.contacts.ImportContacts(
                contacts=contacts
            )
        )

        return imported_contacts