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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 _check_prompts(pre_prompt, post_prompt):
    '''Check that the prompts are strings'''
    if not isinstance(pre_prompt, str):
        raise TypeError("The pre_prompt was not a string!")
    if post_prompt is not _NO_ARG and not isinstance(post_prompt, str):
        raise TypeError("The post_prompt was given and was not a string!")