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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 rewind_body(prepared_request):
 """Move file pointer back to its recorded starting position so it can be read again on redirect. """

    body_seek = getattr(prepared_request.body, 'seek', None)
    if body_seek is not None and isinstance(prepared_request._body_position, integer_types):
        try:
            body_seek(prepared_request._body_position)
        except (IOError, OSError):
            raise UnrewindableBodyError("An error occurred when rewinding request "
                                        "body for redirect.")
    else:
        raise UnrewindableBodyError("Unable to rewind request body for redirect.")