frappy_psi.tcs: minor fixes

cfg/tcs_cfg.py

@@ -21,4 +21,4 @@ Mod('mix_htr',
     'mixing chamber heater',
     io='io',
     channel=3,
-    )
+    )

frappy_psi/tcs.py

@@ -18,8 +18,7 @@
 #   Anik Stark <anik.stark@psi.ch>
 # *****************************************************************************
 
-from frappy.core import StringIO, HasIO, Writable, Parameter, Property, FloatRange, IntRange, BoolType, \
-    ERROR
+from frappy.core import StringIO, HasIO, Writable, Parameter, Property, FloatRange, IntRange, BoolType
 from frappy.errors import CommunicationFailedError, HardwareError
 from frappy.ctrlby import WrapControlledBy