Mercury not recognized

[AlanReviews]

I am trying to extract the mercury element's attributes.

Here is a sample of my code when I am trying to extract the mercury element:

import periodic
from periodic import element
someElement = element('Mercury')
print(someElement.symbol)

I got this error:
Traceback (most recent call last):
File "c:\Users\Alan\Documents\VSCodeWorkspace\testing\periodic-testing.py", line 4, in
print(someElement.symbol)
AttributeError: 'NoneType' object has no attribute 'symbol