Rule Description KPI URL
E0102-alreadyDefinedLine Prohibits the redefinition of functions, classes and methods. Understandability
E0105-yieldOutsideFunction A yield statement is found outside a function or method. Understandability
E0106-returnWithArgInsideGenerator A return statement with an argument is found in a generator function or method (e.g. with some yield statements). Understandability
E0202-hiddenMethod A class defines a method which is hidden by an instance attribute with the same name. Understandability
E0203-accessToMethodBeforeDefinition An instance member is accessed before it’s actually assigned. Understandability
E0211-noArgumentInMethod A method which should have the bound instance as first argument has no argument defined. Accuracy
E0213-selfArgumentMissing The first argument of a (instance) method has a name other than self. Understandability
E0221-resolvedInterfaceIsNotClass A class claims to implement an interface which is not a class. Understandability
E0222-missingMethodFromInterface A method declared in an interface is missing from a class implementing this interface. Understandability
E0501-noEncodingSpecified Non-ASCII characters found but no encoding specified Accuracy
E0502-wrongEncoding Wrong encoding specified Accuracy
E0503-unknownEncoding Unknown encoding specified Accuracy
E0601-localVarUserBeforeAssignment Avoid using a local variable from being accessed before it’s actually assigned. Accuracy
E0602-undefinedVariable An undefined variable is accessed. Accuracy
E0701-incorrectExceptClausesOrder Except clauses are not in the correct order (from the more specific to the more generic). If you don’t fix the order, some exceptions may not be caught by the most specific handler. Accuracy
E0711-notImplementedRaised Avoid raising NotImplemented, NotImplementedError should be raised instead. Understandability
E1102-ObjectNotCallable Avoid invocation of an object that has been inferred to a non-callable object. Robustness
E1111-incorrectAssignmentOfFunction An assigment is done on a function call but the inferred function doesn’t return anything. Understandability
E1301-avoidPartialConversionInString Avoid partial conversion specifiers from being used in string format operations. Understandability
E1304-missingKeyInFormatStringDictionary Avoid mapping for format string operations of having undefined conversion specifiers. Understandability
E1306-insufficientArgForFormatString A format string that uses unnamed conversion specifiers is given too few arguments Understandability
E9900-unsupportedFormatCharacter A character with an unsupported format has been used. Understandability
W0702-noExceptionTypeSpecified An except clause doesn’t specify exceptions type to catch. Accuracy
E0118-nameUsedBeforeDeclaration Emitted when a name is used prior a global declaration, which results in an error since Python 3.6. Understandability
E0237-incorrectAssignmentForSlotClass Used when assigning to an attribute not defined in the class slots. Maintainability
E0401-unableToImportModule Used when pylint has been unable to import a module. Maintainability
E0632-tupleUnpackingUnbalancedTuple Used when there is an unbalanced tuple unpacking in assignment Robustness
E0633-attemptToUnpackNonSequence Used when something which is not a sequence is used in an unpack assignment Maintainability
E1129-contextManagerError Used when an instance in a with statement doesn’t implement the context manager protocol(__enter__/__exit__). Maintainability
E1130-invalidUnaryOperand Emitted when a unary operand is used on an object which does not support this type of operation Maintainability
E1131-unsupportedBinaryOperation Emitted when a binary arithmetic operation between two operands is not supported. Maintainability
E1133-noniterableValueInIteratingContext Used when a non-iterable value is used in place where iterable is expected Robustness
E1134-nonMappingValueInIteratingContext Used when a non-mapping value is used in place where mapping is expected Robustness
E1135-membershipProtocolException Emitted when an instance in membership test expression doesn’t implement membership protocol (__contains__/__iter__/__getitem__) Maintainability
E1136-valueUnsubscriptable Emitted when a subscripted value doesn’t support subscription(i.e. doesn’t define __getitem__ method) Maintainability
E1137-itemAssignmentNotSupported Emitted when an object does not support item assignment (i.e. doesn’t define __setitem__ method) Accuracy
E1138-itemDeletionNotSupported Emitted when an object does not support item deletion (i.e. doesn’t define __delitem__ method) Accuracy
E1139-invalidMetaclassUsed Emitted whenever we can detect that a class is using, as a metaclass, something which might be invalid for using as a metaclass. Maintainability
E1601-printStatementUsed Used when a print statement is used (print is a function in Python 3) Maintainability
E1602-parameterUnpackingSpecified Used when parameter unpacking is specified for a function(Python 3 doesn’t allow it) Maintainability
E1603-implicitUnpackingNotSupported Python3 will not allow implicit unpacking of exceptions in except clauses. Maintainability
E1605-invalidOperatorUsed Used when the deprecated ‘“’ (backtick) operator is used instead of the str() function Maintainability
E1606-usedLongAsSuffix Used when ‘l’ or ‘L’ is used to mark a long integer. This will not work in Python 3, since int and long types have merged. Maintainability
E1607-invalidNegationOperator Used when the deprecated ‘<>’ operator is used instead of ‘!=’. This is removed in Python 3. Maintainability
E1608-oldOctalSyntaxUsed Used when encountering the old octal syntax, removed in Python 3. Maintainability
E1610-notAsciiByteLiteralsNotSupported Used when non-ascii bytes literals are found in a program. They are no longer supported in Python 3. Maintainability
E1701-asyncContextManagerProtocolNotImplemented Used when an async context manager is used with an object that does not implement the async context management protocol. Maintainability
F0202-unableToCheckMethodSignature Used when Pylint has been unable to check methods signature compatibility for an unexpected reason Robustness
E0111-reversedArgumentNotSequenced The first reversed() argument is not a sequence Maintainability
E0113-incorrectStarredAssignment Don’t unpack multiple values using a sole starred assignment target. Maintainability
E0114-useStarredExprInAssignmentTarget Do not use a starred variable expression in other places than an assignment. Maintainability
E0115-nameIsNonlocalAndNonGlobal Do not declare a variable as both nonlocal and global, only one can be picked. Maintainability
E0116-continueInFinallyNotSupported Using continue in a finally statement is a SyntaxError. Maintainability
E0239-inheritingSomethingWhichIsNotAClass Do not inherit from something which is not a class. Understandability
E0240-inconsistentMethodResolutionOrderForClass Avoid defining a class for which a method resolution order could not be determined. Accuracy
E0301-_iterReturnsNonIterator _iter__ should always return an iterator, otherwise an error will occur. Maintainability
E0302-enforceCorrectSignatureForSpecialMethod Enforce correct signature of special methods Understandability
E0704-raiseNotInsideExceptClause Do not place raise in other places than an except clause. Maintainability
E1126-sequenceIndexNotAnInt Always index a sequence with an integer, a slice or an instance providing an __index__ method. Maintainability