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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_sorted_mosaics(dicom_input):
 """ Search all mosaics in the dicom directory, sort and validate them """

    # Order all dicom files by acquisition number
    sorted_mosaics = sorted(dicom_input, key=lambda x: x.AcquisitionNumber)

    for index in range(0, len(sorted_mosaics) - 1):
        # Validate that there are no duplicate AcquisitionNumber
        if sorted_mosaics[index].AcquisitionNumber >= sorted_mosaics[index + 1].AcquisitionNumber:
            raise ConversionValidationError("INCONSISTENT_ACQUISITION_NUMBERS")

    return sorted_mosaics