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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 Git(repository, directory, rev=None, prefix=None, shallow_clone=True):
 """ Get a clone of the given repo Args: repository (str):
 Git URL of the SOURCE repo. directory (str):
 Name of the repo folder on disk. tgt_root (str):
 TARGET folder for the git repo. Defaults to ``CFG["tmpdir"]`` shallow_clone (bool):
 Only clone the repository shallow Defaults to true """

    repository_loc = str(prefix)
    if prefix is None:
        repository_loc = str(CFG["tmp_dir"])

    from benchbuild.utils.cmd import git

    src_dir = local.path(repository_loc) / directory
    if not source_required(src_dir):
        Copy(src_dir, ".")
        return

    extra_param = []
    if shallow_clone:
        extra_param.append("--depth")
        extra_param.append("1")

    git("clone", extra_param, repository, src_dir)
    if rev:
        with local.cwd(src_dir):
            git("checkout", rev)

    update_hash(src_dir)
    Copy(src_dir, ".")
    return repository_loc