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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_build_name(git_path='git'):
 """Find the username of the current builder """

    name,retcode = call(('git', 'config', 'user.name'), returncode=True)
    if retcode:
        name = "Unknown User"
    email,retcode = call(('git', 'config', 'user.email'), returncode=True)
    if retcode:
        email = ""
    return "%s <%s>" % (name, email)