def METHOD_NAME(fileobj):
    """Get Content-MD5 value
    All content will be read from the current position to the end of the
    file. The file will be left open with its seek position at the end
    of the file.
    :param fileobj: A file-like object.
    :returns: RFC-1864-compliant Content-MD5 header value.
    """
    md5 = hashlib.md5()
    for chunk in iter(lambda: fileobj.read(1024 * 1024), b''):
        md5.update(chunk)
    return b64encode(md5.digest()).decode('ascii')