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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 filesize(fileobj):
 """Return the number of bytes in the fileobj. This function seeks to the end of the file, and then back to the original position. """

    current = fileobj.tell()
    fileobj.seek(0, 2)
    end = fileobj.tell()
    fileobj.seek(current)
    return end