Question: what does the m number mean on a pint glass
[{'answer': 'the manufacturing company or site', 'provenance': [{'wikipedia_id': '1892358', 'title': 'Pint glass', 'start_paragraph_id': 18, 'start_character': 472, 'end_paragraph_id': 18, 'end_character': 505, 'bleu_score': 1.0, 'section': 'Section::::United Kingdom law.\n'}]}, {'answer': 'imperial fluid ounces'}, {'provenance': [{'wikipedia_id': '1892358', 'title': 'Pint glass', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 184, 'bleu_score': 0.638372382849281, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 8516963395541345752}, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '1892358', 'title': 'Pint glass', 'start_paragraph_id': 0, 'start_character': 0, 'end_paragraph_id': 0, 'end_character': 0, 'bleu_score': 1.0, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 8516963395541345752}, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '1892358', 'title': 'Pint glass', 'start_paragraph_id': 18, 'start_character': 0, 'end_paragraph_id': 18, 'end_character': 595, 'bleu_score': 0.9199988884061311, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 8516963395541345752}, 'section': 'Section::::United Kingdom law.\n'}]}, {'provenance': [{'wikipedia_id': '1892358', 'title': 'Pint glass', 'section': 'Section::::United Kingdom law.\n', 'start_paragraph_id': 18, 'end_paragraph_id': 18, 'meta': {'evidence_span': ['the manufacturing company or site', 'United Kingdom law requires certain steps be taken to ensure that a pint of beer is indeed a pint. Though this can be achieved using "metered dispense" (calibrated pumps), the more common solution is to use certified one-pint glasses. Until recently these had a crown stamp indicating that the certification had been done by an agency of the Crown. The number etched upon the glasses stands for the manufacturing company or site.']}}]}]