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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_dependency_definition(task_id, dependencies):
 """ Internal helper collects all the dependencies of the task, and returns the Airflow equivalent python sytax for specifying them. """

    set_upstream_statements = ''
    for dependency in dependencies:
      set_upstream_statements = set_upstream_statements + \
          '{0}.set_upstream({1})'.format(task_id, dependency) + '\n'
    return set_upstream_statements