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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 validate_property_directives(directives):
 """Validate the directives that appear at a property field."""

    for directive_name in six.iterkeys(directives):
        if directive_name in VERTEX_ONLY_DIRECTIVES:
            raise GraphQLCompilationError(
                u'Found vertex-only directive {} set on property.'.format(directive_name))