Possible null reference return.

Possible null reference argument for parameter 'parser' in 'TokenListParser<PythonToken, PythonTypeSpec?> Combinators.OptionalOrDefault<PythonToken, PythonTypeSpec?>(TokenListParser<PythonToken, PythonTypeSpec?> parser, PythonTypeSpec? defaultValue = null)'.

Possible null reference argument for parameter 'parser' in 'TokenListParser<PythonToken, PythonTypeSpec?> Combinators.OptionalOrDefault<PythonToken, PythonTypeSpec?>(TokenListParser<PythonToken, PythonTypeSpec?> parser, PythonTypeSpec? defaultValue = null)'.

Possible null reference argument for parameter 'parser' in 'TokenListParser<PythonToken, PythonTypeSpec?[]> Combinators.ManyDelimitedBy<PythonToken, PythonTypeSpec?, Token<PythonToken>>(TokenListParser<PythonToken, PythonTypeSpec?> parser, TokenListParser<PythonToken, Token<PythonToken>> delimiter, TokenListParser<PythonToken, Token<PythonToken>>? end = null)'.

Argument of type 'TokenListParser<PythonToken, PythonTypeSpec?[]>' cannot be used for parameter 'parser' of type 'TokenListParser<PythonToken, PythonTypeSpec?[]?>' in 'TokenListParser<PythonToken, PythonTypeSpec?[]?> Combinators.OptionalOrDefault<PythonToken, PythonTypeSpec?[]?>(TokenListParser<PythonToken, PythonTypeSpec?[]?> parser, PythonTypeSpec?[]? defaultValue = null)' due to differences in the nullability of reference types.

Nullability of type of parameter 'obj' doesn't match overridden member (possibly because of nullability attributes).

The type 'TKey' cannot be used as type parameter 'TKey' in the generic type or method 'Dictionary<TKey, TValue>'. Nullability of type argument 'TKey' doesn't match 'notnull' constraint.

The type 'TKey' cannot be used as type parameter 'TKey' in the generic type or method 'ReadOnlyDictionary<TKey, TValue>'. Nullability of type argument 'TKey' doesn't match 'notnull' constraint.

A stable release of a package should not have a prerelease dependency. Either modify the version spec of dependency "pythonnet