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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 _get_context(keyspaces, connections):
 """Return all the execution contexts"""


    if keyspaces:
        if not isinstance(keyspaces, (list, tuple)):
            raise ValueError('keyspaces must be a list or a tuple.')

    if connections:
        if not isinstance(connections, (list, tuple)):
            raise ValueError('connections must be a list or a tuple.')

    keyspaces = keyspaces if keyspaces else [None]
    connections = connections if connections else [None]

    return product(connections, keyspaces)