exec(open('C:/Arundhati/Automation Test Script/Radio Signal/QGIS_Test.py'.encode('utf-8')).read())
Traceback (most recent call last):
  File "C:PROGRA~1QGIS3~1.0appsPython36libcode.py", line 91, in runcode
    exec(code, self.locals)
  File "<input>", line 1, in <module>
  File "<string>", line 12, in <module>
AttributeError: 'QgsVectorLayer' object has no attribute 'layer'

from qgis.core import *
import qgis.utils
import sys

QgsApplication.setPrefixPath("C:/Program Files/QGIS 3.0", True)
qgs = QgsApplication([], False) ###
qgs.initQgis() ###

_layer1 = QgsVectorLayer("C:/Arundhati/Automation Test Script/Radio Signal/SIGNAL.shp", "SIGNAL", "ogr")

print("I am here" + _layer1.layer.wkbType())


_writer1 = QgsVectorFileWriter("C:/Arundhati/Automation Test Script/Radio Signal/SIGNAL.shp", 'utf-8', _layer1.fields(),Qgis.WKBPoint,QgsCoordinateReferenceSystem(),'ESRI Shapefile')

#add a feature
fet = QgsFeature()
fet.setGeometry(QgsGeometry.fromPoint(QgsPoint(10,10)))
fet.setAttributes([1,"text"])
_writer1.addFeature(fet)

del _writer1

qgs.exitQgis()