How to use pyca - 2 common examples

def connected_cb(self, isconnected):
        """
        Callback to run whenever the connection state of our pv changes.

        :param isconnected: True if we are connected, False otherwise.
        :type isconnected:  bool
        """
        self.connected = isconnected
        self.send_connection_state(isconnected)
        if isconnected:
            self.epics_type = self.pv.type()
            self.count = self.pv.count or 1

            # Get the control info for the PV.
            self.pv.get_data(True, -1.0, self.count)
            pyca.flush_io()
            if self.epics_type == "DBF_ENUM":
                self.pv.get_enum_strings(-1.0)
            if not self.pv.ismonitored:
                self.pv.monitor()
            self.python_type = type_map.get(self.epics_type)
            if self.python_type is None:
                raise Exception("Unsupported EPICS type {0} for pv {1}".format(
                    self.epics_type, self.pv.name))

def put_value(self, value):
        """
        Set our PV's value in EPICS.

        :param value: The value we'd like to put to our PV.
        :type value:  int or float or str or np.ndarray, depending on our
                      record type.
        """
        if self.count == 1:
            value = self.python_type(value)
        try:
            self.pv.put(value)
        except pyca.caexc as e:
            print("pyca error: {}".format(e))