How to use the @mapbox/cloudfriend.select function in @mapbox/cloudfriend

Principal: {
             Service: [ "ec2.amazonaws.com" ]
          },
          Action: [ "sts:AssumeRole" ]
        }]
      },
      Policies: [{
        PolicyName: "AccessToDatabaseDump",
        PolicyDocument: {
          Version: "2012-10-17",
          Statement:[{
            Action: [ 's3:ListBucket'],
            Effect: 'Allow',
            Resource: [ cf.join('',
              ['arn:aws:s3:::',
                cf.select(0,
                  cf.split('/',
                    cf.select(1,
                      cf.split('s3://', cf.ref('DatabaseDump'))
                    )
                  )
                )
              ]
            )]
          }, {
            Action: [
              's3:GetObject',
              's3:GetObjectAcl',
              's3:ListObjects',
              's3:ListBucket'
            ],
            Effect: 'Allow',

},
          Action: [ "sts:AssumeRole" ]
        }]
      },
      Policies: [{
        PolicyName: "AccessToDatabaseDump",
        PolicyDocument: {
          Version: "2012-10-17",
          Statement:[{
            Action: [ 's3:ListBucket'],
            Effect: 'Allow',
            Resource: [ cf.join('',
              ['arn:aws:s3:::',
                cf.select(0,
                  cf.split('/',
                    cf.select(1,
                      cf.split('s3://', cf.ref('DatabaseDump'))
                    )
                  )
                )
              ]
            )]
          }, {
            Action: [
              's3:GetObject',
              's3:GetObjectAcl',
              's3:ListObjects',
              's3:ListBucket'
            ],
            Effect: 'Allow',
            Resource: [cf.join('',
              ['arn:aws:s3:::',

)
                  )
                )
              ]
            )]
          }, {
            Action: [
              's3:GetObject',
              's3:GetObjectAcl',
              's3:ListObjects',
              's3:ListBucket'
            ],
            Effect: 'Allow',
            Resource: [cf.join('',
              ['arn:aws:s3:::',
                cf.select(1,
                  cf.split('s3://', cf.ref('DatabaseDump'))
              )]
            )]
          }]
        }
      }],
      RoleName: cf.join('-', [cf.stackName, 'ec2', 'database-dump-access', 'role'])
    }
  },
  TaskingManagerEC2InstanceProfile: {
     Type: "AWS::IAM::InstanceProfile",
     Properties: {
        Roles: cf.if('DatabaseDumpFileGiven', [cf.ref('TaskingManagerDatabaseDumpAccessRole')], [cf.ref('TaskingManagerEC2Role')]),
        InstanceProfileName: cf.join('-', [cf.stackName, 'ec2', 'instance', 'profile'])
     }
  },

Effect: 'Allow',
            Resource: ['arn:aws:cloudformation:*']
          }]
        }
      }, {
        PolicyName: "AccessToDatabaseDump",
        PolicyDocument: {
          Version: "2012-10-17",
          Statement:[{
            Action: [ 's3:ListBucket'],
            Effect: 'Allow',
            Resource: [ cf.join('',
              ['arn:aws:s3:::',
                cf.select(0,
                  cf.split('/',
                    cf.select(1,
                      cf.split('s3://', cf.ref('DatabaseDump'))
                    )
                  )
                )
              ]
            )]
          }, {
            Action: [
              's3:GetObject',
              's3:GetObjectAcl',
              's3:ListObjects',
              's3:ListBucket'
            ],
            Effect: 'Allow',
            Resource: [cf.join('',
              ['arn:aws:s3:::',

)
                  )
                )
              ]
            )]
          }, {
            Action: [
              's3:GetObject',
              's3:GetObjectAcl',
              's3:ListObjects',
              's3:ListBucket'
            ],
            Effect: 'Allow',
            Resource: [cf.join('',
              ['arn:aws:s3:::',
                cf.select(1,
                  cf.split('s3://', cf.ref('DatabaseDump'))
              )]
            )]
          }]
        }
      }],
      RoleName: cf.join('-', [cf.stackName, 'ec2', 'database-dump-access', 'role'])
    }
  },
  TaskingManagerEC2InstanceProfile: {
     Type: "AWS::IAM::InstanceProfile",
     Properties: {
        Roles: cf.if('DatabaseDumpFileGiven', [cf.ref('TaskingManagerEC2Role'), cf.ref('TaskingManagerDatabaseDumpAccessRole')], [cf.ref('TaskingManagerEC2Role')]),
        InstanceProfileName: cf.join('-', [cf.stackName, 'ec2', 'instance', 'profile'])
     }
  },

'cloudformation:DescribeStackResource'
            ],
            Effect: 'Allow',
            Resource: ['arn:aws:cloudformation:*']
          }]
        }
      }, {
        PolicyName: "AccessToDatabaseDump",
        PolicyDocument: {
          Version: "2012-10-17",
          Statement:[{
            Action: [ 's3:ListBucket'],
            Effect: 'Allow',
            Resource: [ cf.join('',
              ['arn:aws:s3:::',
                cf.select(0,
                  cf.split('/',
                    cf.select(1,
                      cf.split('s3://', cf.ref('DatabaseDump'))
                    )
                  )
                )
              ]
            )]
          }, {
            Action: [
              's3:GetObject',
              's3:GetObjectAcl',
              's3:ListObjects',
              's3:ListBucket'
            ],
            Effect: 'Allow',

Properties: {
        AutoScalingGroupName: cf.ref('TaskingManagerASG'),
        PolicyType: 'TargetTrackingScaling',
        TargetTrackingConfiguration: {
          TargetValue: 600,
          PredefinedMetricSpecification: {
            PredefinedMetricType: 'ALBRequestCountPerTarget',
            ResourceLabel: cf.join('/', [
              cf.select(1,
                cf.split('loadbalancer/',
                  cf.select(5,
                    cf.split(':', cf.ref("TaskingManagerLoadBalancer"))
                  )
                )
              ),
              cf.select(5,
                cf.split(':', cf.ref("TaskingManagerTargetGroup"))
              )
            ])
          }
        },
        Cooldown: 600
      }
  },
  TaskingManagerLaunchConfiguration: {
    Type: "AWS::AutoScaling::LaunchConfiguration",
    Metadata: {
      "AWS::CloudFormation::Init": {
        "configSets": {
          "default": [
            "01_setupCfnHup", 
            "02_config-amazon-cloudwatch-agent",

}
    }
  },
  TaskingManagerScaleUp: {
      Type: "AWS::AutoScaling::ScalingPolicy",
      Properties: {
        AutoScalingGroupName: cf.ref('TaskingManagerASG'),
        PolicyType: 'TargetTrackingScaling',
        TargetTrackingConfiguration: {
          TargetValue: 600,
          PredefinedMetricSpecification: {
            PredefinedMetricType: 'ALBRequestCountPerTarget',
            ResourceLabel: cf.join('/', [
              cf.select(1,
                cf.split('loadbalancer/',
                  cf.select(5,
                    cf.split(':', cf.ref("TaskingManagerLoadBalancer"))
                  )
                )
              ),
              cf.select(5,
                cf.split(':', cf.ref("TaskingManagerTargetGroup"))
              )
            ])
          }
        },
        Cooldown: 600
      }
  },
  TaskingManagerLaunchConfiguration: {
    Type: "AWS::AutoScaling::LaunchConfiguration",
    Metadata: {