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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 fromstring(text, schema=None):
 """Parses a KML text string This function parses a KML text string and optionally validates it against a provided schema object"""

    if schema:
        parser = objectify.makeparser(schema = schema.schema)
        return objectify.fromstring(text, parser=parser)
    else:
        return objectify.fromstring(text)