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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 _assert_explicit_vr(dicom_input):
 """ Assert that explicit vr is used """

    if settings.validate_multiframe_implicit:
        header = dicom_input[0]
        if header.file_meta[0x0002, 0x0010].value == '1.2.840.10008.1.2':
            raise ConversionError('IMPLICIT_VR_ENHANCED_DICOM')