Problems with smbus

[GeralDennis]

I need help!
When a run the script I obtain the following error:

Traceback (most recent call last):
File "chirp.py", line 21, in
import smbus
ImportError: No module named smbus

I've installed python 2.7.18 and when I want to install smbus library using "sudo apt-get install python-smbus", I obtain the following error:

Reading package lists... Done
Building dependency tree... Done
Reading state information... Done
Package python-smbus is not available, but is referred to by another package.
This may mean that the package is missing, has been obsoleted, or
is only available from another source

E: Package 'python-smbus' has no installation candidate

Thanks in advance for your help.