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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 add_quota(self, quota):
 """Adds an internal tracking reference for the given quota."""

        if quota.limit in (None, -1, float('inf')):
            # Handle "unlimited" quotas.
            self.usages[quota.name]['quota'] = float("inf")
            self.usages[quota.name]['available'] = float("inf")
        else:
            self.usages[quota.name]['quota'] = int(quota.limit)