Pylint checking

pip install pylint

len = 42
print(len)

pylint bad.py

************* Module bad
bad.py:1:0: C0114: Missing module docstring (missing-module-docstring)
bad.py:2:0: W0622: Redefining built-in 'len' (redefined-builtin)
bad.py:2:0: C0103: Constant name "len" doesn't conform to UPPER_CASE naming style (invalid-name)

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Your code has been rated at -5.00/10 (previous run: -5.00/10, +0.00)