Replace io.open() with builtin open()

`io.open` is an alias for `open` anyway.

Author: pavoljuhas

cirq-aqt/setup.py

@@ -12,7 +12,6 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-import io
 import runpy
 
 from setuptools import find_packages, setup
@@ -28,7 +27,7 @@
 )
 
 # README file as long_description.
-long_description = io.open('README.md', encoding='utf-8').read()
+long_description = open('README.md', encoding='utf-8').read()
 
 # Read in requirements
 requirements = open('requirements.txt').readlines()

cirq-core/setup.py

@@ -12,7 +12,6 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-import io
 import runpy
 
 from setuptools import find_packages, setup
@@ -29,7 +28,7 @@
 )
 
 # README file as long_description.
-long_description = io.open('README.md', encoding='utf-8').read()
+long_description = open('README.md', encoding='utf-8').read()
 
 # Read in requirements
 requirements = open('requirements.txt').readlines()

cirq-ionq/setup.py

@@ -12,7 +12,6 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-import io
 import runpy
 
 from setuptools import find_packages, setup
@@ -26,7 +25,7 @@
 description = 'A Cirq package to simulate and connect to IonQ quantum computers'
 
 # README file as long_description.
-long_description = io.open('README.md', encoding='utf-8').read()
+long_description = open('README.md', encoding='utf-8').read()
 
 # Read in requirements
 requirements = open('requirements.txt').readlines()

cirq-pasqal/setup.py

@@ -12,7 +12,6 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-import io
 import runpy
 
 from setuptools import find_packages, setup
@@ -26,7 +25,7 @@
 description = 'A Cirq package to simulate and connect to Pasqal quantum computers'
 
 # README file as long_description.
-long_description = io.open('README.md', encoding='utf-8').read()
+long_description = open('README.md', encoding='utf-8').read()
 
 # Read in requirements
 requirements = open('requirements.txt').readlines()

cirq-rigetti/setup.py

@@ -12,7 +12,6 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-import io
 import runpy
 
 from setuptools import find_packages, setup
@@ -26,7 +25,7 @@
 description = 'A Cirq package to simulate and connect to Rigetti quantum computers and Quil QVM'
 
 # README file as long_description.
-long_description = io.open('README.md', encoding='utf-8').read()
+long_description = open('README.md', encoding='utf-8').read()
 
 # Read in requirements
 requirements = open('requirements.txt').readlines()