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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 check_p_equals_zero(text):
 """Check for p = 0.000."""

    err = "psychology.p_equals_zero"
    msg = "Unless p really equals zero, you should use more decimal places."

    list = [
        "p = 0.00",
        "p = 0.000",
        "p = 0.0000",
    ]

    return existence_check(text, list, err, msg, join=True)