def METHOD_NAME(self, type_repr: str) -> Optional[Type[ColType]]:
    nullable_prefix = "Nullable("
    if type_repr.startswith(nullable_prefix):
        type_repr = type_repr[len(nullable_prefix) :].rstrip(")")
    if type_repr.startswith("Decimal"):
        type_repr = "Decimal"
    elif type_repr.startswith("FixedString"):
        type_repr = "FixedString"
    elif type_repr.startswith("DateTime64"):
        type_repr = "DateTime64"
    return self.TYPE_CLASSES.get(type_repr)