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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 edit(self, changelist=0):
 """Checks out the file :param changelist: Optional changelist to checkout the file into :type changelist: :class:`.Changelist` """

        command = 'reopen' if self.action in ('add', 'edit') else 'edit'
        if int(changelist):
            self._connection.run([command, '-c', str(changelist.change), self.depotFile])
        else:
            self._connection.run([command, self.depotFile])

        self.query()