Azure Pipeline - How to make delayForMinutes task use value from variable instead of hardcoded value

Question

How to make Delay task take value from variable instead of hardcoded value for delayForMinutes input?
When i do following, it works fine:

- job: WaitForDeploy
    dependsOn: Main
    pool: Server
    steps:
    - task: Delay@1
      inputs:
        delayForMinutes: '1'

but when i do it like this it does not:

- job: WaitForDeploy
    dependsOn: Main
    pool: Server
    steps:
    - task: Delay@1
      inputs:
        delayForMinutes: '$(SleepCount)'

$(SleepCount) is defined in variables as empty string and later on is passed from python script to pipeline via: print(f'##vso[task.setvariable variable=SleepCount]{delay_seconds}') I am printing this out in previos job and it shows intiger correctly:

- script: 'echo $(SleepCount)'
      displayName: "print_sleep_count"

it looks like this variable value is not passed beyond job where i return it from python script, how to pass it?
This do not work:

variables:
  SleepCount: ""

jobs:
  - job: Main
    pool:
      name: 'CDaaSLinux'

    [...]

    - task: PythonScript@0
      inputs:
        scriptSource: 'filePath'
        scriptPath: '$(Build.SourcesDirectory)/sleep_count.py'
      env:
        ACTUAL_START_DATE: $(ActualStartDate_value)

    - script: 'echo $(SleepCount)'
      name: setVariable
      displayName: "print_sleep_count"

    - script: 'echo "Waiting for Deploy for $(SleepCount) minutes"'
      displayName: "Deploy_message_for_user"
      
  - job: WaitForDeploy
    dependsOn: Main
    variables:
      SleepCount: $[ dependencies.Main.outputs['setVariable.SleepCount']]
    pool: Server
    steps:
    - task: Delay@1
      inputs:
        delayForMinutes: '$(SleepCount)'

Answer 1

In order to use a variable in a different stage/job you need to set the isoutput flag when setting the variable

print(f'##vso[task.setvariable variable=SleepCount;isoutput=true]{delay_seconds}')

Set an output variable for use in future jobs