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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 GetBudget(self, client_customer_id, budget_id):
 """Return a Budget with the associated budgetId. Args: client_customer_id: str Client Customer Id to which the budget belongs. budget_id: str id of the budget we want to examine. Returns: Budget A Budget data object. """

    self.client.SetClientCustomerId(client_customer_id)
    selector = {
        'fields': ['BudgetId', 'BudgetName', 'BudgetStatus', 'Amount',
                   'DeliveryMethod', 'BudgetReferenceCount',
                   'IsBudgetExplicitlyShared'],
        'predicates': [
            {
                'field': 'BudgetId',
                'operator': 'EQUALS',
                'values': [budget_id]
            }
        ]
    }
    budgets = self.client.GetService('BudgetService').get(selector)

    if int(budgets['totalNumEntries']) > 0:
      return budgets['entries'][0]
    else:
      return None