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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 disasters_sim(early_mean=early_mean, late_mean=late_mean, switchpoint=switchpoint):
 """Coal mining disasters sampled from the posterior predictive distribution"""

    return concatenate((pm.rpoisson(early_mean, size=switchpoint), pm.rpoisson(
        late_mean, size=n - switchpoint)))