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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(body, body_pos):
 """ Attempt to rewind body to a certain position. Primarily used for request redirects and retries. :param body: File-like object that supports seek. :param int pos: Position to seek to in file. """

    body_seek = getattr(body, 'seek', None)
    if body_seek is not None and isinstance(body_pos, integer_types):
        try:
            body_seek(body_pos)
        except (IOError, OSError):
            raise UnrewindableBodyError("An error occurred when rewinding request "
                                        "body for redirect/retry.")
    elif body_pos is _FAILEDTELL:
        raise UnrewindableBodyError("Unable to record file position for rewinding "
                                    "request body during a redirect/retry.")
    else:
        raise ValueError("body_pos must be of type integer, "
                         "instead it was %s." % type(body_pos))