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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 to_python(self, value):
 """Converts any value to a base.Version field."""

        if value is None or value == '':
            return value
        if isinstance(value, base.Version):
            return value
        if self.coerce:
            return base.Version.coerce(value, partial=self.partial)
        else:
            return base.Version(value, partial=self.partial)