def get_attribute_value(self, attribute_marker: str) -> str | None:
        """
        Returns the value of the attribute. If multiple values are present,
        the most commonly observed one is returned.
        """
        # Attributes are recorded as a dict, with the key representing an
        # observation, and the value representing the duration that it was
        # observed. the first character of the observation is the 'marker' -
        # the type of the attribute, the rest is data.
        matching_attributes = [
            a_tuple
            for a_tuple in self.attributes.items()
            if a_tuple[0].startswith(attribute_marker)
        ]

        if len(matching_attributes) == 0:
            return None

        top_attribute, _ = max(matching_attributes, key=lambda a: a[1])

        # strip off the marker, return the data
        return top_attribute[1:]

        Returns the value of the attribute. If multiple values are present,
        the most commonly observed one is returned.
        
pyinstrument/frame.py