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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 create_with_validation (raw_properties):
 """ Creates new 'PropertySet' instances after checking that all properties are valid and converting implicit properties into gristed form. """

    assert is_iterable_typed(raw_properties, basestring)
    properties = [property.create_from_string(s) for s in raw_properties]
    property.validate(properties)

    return create(properties)