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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 from_iterable(cls, target_types, address_mapper, adaptor_iter):
 """Create a new DependentGraph from an iterable of TargetAdaptor subclasses."""

    inst = cls(target_types, address_mapper)
    all_valid_addresses = set()
    for target_adaptor in adaptor_iter:
      inst._inject_target(target_adaptor)
      all_valid_addresses.add(target_adaptor.address)
    inst._validate(all_valid_addresses)
    return inst