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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 _make_context(context=None):
 """Create the namespace of items already pre-imported when using shell. Accepts a dict with the desired namespace as the key, and the object as the value. """

    namespace = {'db': db, 'session': db.session}
    namespace.update(_iter_context())

    if context is not None:
        namespace.update(context)

    return namespace