pi@raspberrypi:~ $ sudo pip3 install mfrc522
Looking in indexes: https://pypi.org/simple, https://www.piwheels.org/simple
Requirement already satisfied: mfrc522 in /usr/local/lib/python3.7/dist-packages (0.0.7)
Requirement already satisfied: RPi.GPIO in /usr/lib/python3/dist-packages (from mfrc522) (0.7.0)
Requirement already satisfied: spidev in /usr/lib/python3/dist-packages (from mfrc522) (3.4)
pi@raspberrypi:~ $ python3
Python 3.7.3 (default, Dec 20 2019, 18:57:59) 
[GCC 8.3.0] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> from mfrc522 import SimpleMFRC522
>>> reader = SimpleMFRC522()
/usr/local/lib/python3.7/dist-packages/mfrc522/MFRC522.py:151: RuntimeWarning: This channel is already in use, continuing anyway.  Use GPIO.setwarnings(False) to disable warnings.
  GPIO.setup(pin_rst, GPIO.OUT)
>>> reader.write ('parcel1')
(1223443245, 'parcel1')         
>>> reader.read() 
(1223443245, 'parcel1         ')
>>>^Z
[2]+  Stopped                 python3
pi@raspberrypi:~ $ python
Python 2.7.16 (default, Oct 10 2019, 22:02:15) 
[GCC 8.3.0] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> from mfrc522 import SimpleMFRC522
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
ImportError: No module named mfrc522
>>> RFIDModule = SimpleMFRC522()
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
NameError: name 'SimpleMFRC522' is not defined
>>> XZ
[3]+  Stopped                 python