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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 is_executable(command):
 """Returns if a command matches an executable on the PATH"""


    paths = os.environ.get("PATH", "").split(os.path.pathsep)
    candidates = [command] + [os.path.join(p, command) for p in paths]
    return any(os.access(path, os.X_OK) for path in candidates)