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func (r *Reader) AddNonTrailingChecksum(cs *Checksum, ignoreValue bool) error {
	if cs == nil {
		return nil
	}
	r.contentHash = *cs
	if ignoreValue {
		// Do not validate, but allow for transfer
		return nil
	}

	r.contentHasher = cs.Type.Hasher()
	if r.contentHasher == nil {
		return ErrInvalidChecksum
	}
	return nil
}

func (r *Reader) Read(p []byte) (int, error) {

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      (except as stated in this section) patent license to make, have made,
      use, offer to sell, sell, import, and otherwise transfer the Work,
      where such license applies only to those patent claims licensable
      by such Contributor that are necessarily infringed by their
      Contribution(s) alone or by combination of their Contribution(s)

      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
      (except as stated in this section) patent license to make, have made,
      use, offer to sell, sell, import, and otherwise transfer the Work,
      where such license applies only to those patent claims licensable
      by such Contributor that are necessarily infringed by their
      Contribution(s) alone or by combination of their Contribution(s)

      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
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      use, offer to sell, sell, import, and otherwise transfer the Work,
      where such license applies only to those patent claims licensable
      by such Contributor that are necessarily infringed by their
      Contribution(s) alone or by combination of their Contribution(s)