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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 _find_field(cls, field, doc):
 """Find the field in the document which matches the given field. The field may be in dot notation, eg "a.b.c". Returns a list with a single tuple (path, field_value) or the empty list if the field is not present. """

        path = field.split(".")
        try:
            for key in path:
                doc = doc[key]
            return [(path, doc)]
        except (KeyError, TypeError):
            return []