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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 update_stampfile_hook(self, dependencies):
 # suppress(no-self-use) """Loop over all dependencies and store hash for each of them."""

        hashes = {d: _sha1_for_file(d) for d in dependencies
                  if os.path.exists(d)}
        with open(self._stamp_file_hashes_path, "wb") as hashes_file:
            hashes_file.write(json.dumps(hashes).encode("utf-8"))