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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 build_map_type_validator(item_validator):
 """Return a function which validates that the value is a mapping of items. The function should return pairs of items that will be passed to the `dict` constructor. """

    def validate_mapping(value):
        return dict(item_validator(item) for item in validate_list(value))
    return validate_mapping