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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 get_git_branch(git_path='git'):
 """Returns the name of the current git branch """

    branch_match = call((git_path, 'rev-parse', '--symbolic-full-name', 'HEAD'))
    if branch_match == "HEAD":
        return None
    else:
        return os.path.basename(branch_match)