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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 load_env(print_vars=False):
 """Load environment variables from a .env file, if present. If an .env file is found in the working directory, and the listed environment variables are not already set, they will be set according to the values listed in the file. """

    env_file = os.environ.get('ENV_FILE', '.env')
    try:
        variables = open(env_file).read().splitlines()
        for v in variables:
            if '=' in v:
                key, value = v.split('=', 1)
                if key.startswith('#'):
                    continue
                if key not in os.environ:
                    if value.startswith('"') and value.endswith('"') or \
                                    value.startswith("'") and value.endswith("'"):
                        os.environ[key] = ast.literal_eval(value)
                    else:
                        os.environ[key] = value
                    if print_vars:
                        print(key, os.environ[key])
    except IOError:
        pass