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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 calculate_file_access_time(workflow_workspace):
 """Calculate access times of files in workspace."""

    access_times = {}
    for subdir, dirs, files in os.walk(workflow_workspace):
        for file in files:
            file_path = os.path.join(subdir, file)
            access_times[file_path] = os.stat(file_path).st_atime
    return access_times