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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 GetHasherClasses(cls, hasher_names=None):
 """Retrieves the registered hashers. Args: hasher_names (list[str]):
 names of the hashers to retrieve. Yields: tuple: containing: str: parser name type: next hasher class. """

    for hasher_name, hasher_class in iter(cls._hasher_classes.items()):
      if not hasher_names or hasher_name in hasher_names:
        yield hasher_name, hasher_class