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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 delete(cls, repo, *heads, **kwargs):
 """Delete the given heads :param force: If True, the heads will be deleted even if they are not yet merged into the main development stream. Default False"""

        force = kwargs.get("force", False)
        flag = "-d"
        if force:
            flag = "-D"
        repo.git.branch(flag, *heads)