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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def new(arg_name, annotated_with=None):
 """Creates a BindingKey. Args: arg_name: the name of the bound arg annotation: an Annotation, or None to create an unannotated binding key Returns: a new BindingKey """

    if annotated_with is not None:
        annotation = annotations.Annotation(annotated_with)
    else:
        annotation = annotations.NO_ANNOTATION
    return BindingKey(arg_name, annotation)