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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 populate_all():
 """Fetch and store all metadata from the AFIP."""

    ReceiptType.objects.populate()
    ConceptType.objects.populate()
    DocumentType.objects.populate()
    VatType.objects.populate()
    TaxType.objects.populate()
    CurrencyType.objects.populate()