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diff --git a/azure/aria/aria-extension-cloudify/src/aria/aria/modeling/functions.py b/azure/aria/aria-extension-cloudify/src/aria/aria/modeling/functions.py
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+# Licensed to the Apache Software Foundation (ASF) under one or more
+# contributor license agreements.  See the NOTICE file distributed with
+# this work for additional information regarding copyright ownership.
+# The ASF licenses this file to You under the Apache License, Version 2.0
+# (the "License"); you may not use this file except in compliance with
+# the License.  You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""
+Mechanism for evaluating intrinsic functions.
+"""
+from ..parser.exceptions import InvalidValueError
+from ..parser.consumption import ConsumptionContext
+from ..utils.collections import OrderedDict
+from ..utils.type import full_type_name
+from . import exceptions
+
+
+class Function(object):
+    """
+    Base class for intrinsic functions. Serves as a placeholder for a value that should eventually
+    be derived by "evaluating" (calling) the function.
+
+    Note that this base class is provided as a convenience and you do not have to inherit it: any
+    object with an ``__evaluate__`` method would be treated similarly.
+    """
+
+    @property
+    def as_raw(self):
+        raise NotImplementedError
+
+    def __evaluate__(self, container_holder):
+        """
+        Evaluates the function if possible.
+
+        :rtype: :class:`Evaluation` (or any object with ``value`` and ``final`` properties)
+        :raises CannotEvaluateFunctionException: if cannot be evaluated at this time (do *not* just
+         return ``None``)
+        """
+
+        raise NotImplementedError
+
+    def __deepcopy__(self, memo):
+        # Circumvent cloning in order to maintain our state
+        return self
+
+
+class Evaluation(object):
+    """
+    An evaluated :class:`Function` return value.
+
+    :ivar value: evaluated value
+    :ivar final: whether the value is final
+    :vartype final: boolean
+    """
+
+    def __init__(self, value, final=False):
+        self.value = value
+        self.final = final
+
+
+def evaluate(value, container_holder, report_issues=False): # pylint: disable=too-many-branches
+    """
+    Recursively attempts to call ``__evaluate__``. If an evaluation occurred will return an
+    :class:`Evaluation`, otherwise it will be ``None``. If any evaluation is non-final, then the
+    entire evaluation will also be non-final.
+
+    The ``container_holder`` argument should have three properties: ``container`` should return
+    the model that contains the value, ``service`` should return the containing
+    :class:`~aria.modeling.models.Service` model or None, and ``service_template`` should return the
+    containing :class:`~aria.modeling.models.ServiceTemplate` model or ``None``.
+    """
+
+    evaluated = False
+    final = True
+
+    if hasattr(value, '__evaluate__'):
+        try:
+            evaluation = value.__evaluate__(container_holder)
+
+            # Verify evaluation structure
+            if (evaluation is None) \
+                or (not hasattr(evaluation, 'value')) \
+                or (not hasattr(evaluation, 'final')):
+                raise InvalidValueError('bad __evaluate__ implementation: {0}'
+                                        .format(full_type_name(value)))
+
+            evaluated = True
+            value = evaluation.value
+            final = evaluation.final
+
+            # The evaluated value might itself be evaluable
+            evaluation = evaluate(value, container_holder, report_issues)
+            if evaluation is not None:
+                value = evaluation.value
+                if not evaluation.final:
+                    final = False
+        except exceptions.CannotEvaluateFunctionException:
+            pass
+        except InvalidValueError as e:
+            if report_issues:
+                context = ConsumptionContext.get_thread_local()
+                context.validation.report(e.issue)
+
+    elif isinstance(value, list):
+        evaluated_list = []
+        for v in value:
+            evaluation = evaluate(v, container_holder, report_issues)
+            if evaluation is not None:
+                evaluated_list.append(evaluation.value)
+                evaluated = True
+                if not evaluation.final:
+                    final = False
+            else:
+                evaluated_list.append(v)
+        if evaluated:
+            value = evaluated_list
+
+    elif isinstance(value, dict):
+        evaluated_dict = OrderedDict()
+        for k, v in value.iteritems():
+            evaluation = evaluate(v, container_holder, report_issues)
+            if evaluation is not None:
+                evaluated_dict[k] = evaluation.value
+                evaluated = True
+                if not evaluation.final:
+                    final = False
+            else:
+                evaluated_dict[k] = v
+        if evaluated:
+            value = evaluated_dict
+
+    return Evaluation(value, final) if evaluated else None