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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 _find_usage_vpcs(self):
 """find usage for VPCs"""

        # overall number of VPCs
        vpcs = self.conn.describe_vpcs()
        self.limits['VPCs']._add_current_usage(
            len(vpcs['Vpcs']),
            aws_type='AWS::EC2::VPC'
        )