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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 connect(self, username=None, passcode=None, wait=False, headers=None, **keyword_headers):
 """ Start a connection. :param str username: the username to connect with :param str passcode: the password used to authenticate with :param bool wait: if True, wait for the connection to be established/acknowledged :param dict headers: a map of any additional headers the broker requires :param keyword_headers: any additional headers the broker requires """

        cmd = CMD_STOMP
        headers = utils.merge_headers([headers, keyword_headers])
        headers[HDR_ACCEPT_VERSION] = self.version

        if self.transport.vhost:
            headers[HDR_HOST] = self.transport.vhost

        if username is not None:
            headers[HDR_LOGIN] = username

        if passcode is not None:
            headers[HDR_PASSCODE] = passcode

        self.send_frame(cmd, headers)

        if wait:
            self.transport.wait_for_connection()
            if self.transport.connection_error:
                raise ConnectFailedException()