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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 startswith(self, prefix, ignore_case=False, options=None):
 """ A query to check if a field starts with a given prefix string **Example**: ``session.query(Spell).filter(Spells.name.startswith("abra", ignore_case=True))`` .. note:: This is a shortcut to .regex('^' + re.escape(prefix)) MongoDB optimises such prefix expressions to use indexes appropriately. As the prefix contains no further regex, this will be optimized by matching only against the prefix. """

        return self.regex('^' + re.escape(prefix), ignore_case=ignore_case, options=options)