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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 is_convertible_with(self, other):
 """Returns true if `other` is convertible with this Dimension. Two known Dimensions are convertible if they have the same value. An unknown Dimension is convertible with all other Dimensions. Args: other: Another Dimension. Returns: True if this Dimension and `other` are convertible. """

        other = as_dimension(other)
        return self._value is None or other.value is None or self._value == other.value