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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_by(self, field, value):
 """ Gets the list of firmware baseline resources managed by the appliance. Optional parameters can be used to filter the list of resources returned. The search is case-insensitive. Args: field: Field name to filter. value: Value to filter. Returns: list: List of firmware baseline resources. """

        firmwares = self.get_all()
        matches = []
        for item in firmwares:
            if item.get(field) == value:
                matches.append(item)
        return matches