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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 remove_notes(data):
 """Omit notes from a DataFrame object, where notes are identified as rows with non-numerical entries in the first column. :param data: DataFrame object to remove notes from :type data: Pandas.DataFrame :return: DataFrame object with no notes :rtype: Pandas.DataFrame """

    has_text = data.iloc[:, 0].astype(str).str.contains('(?!e-)[a-zA-Z]')
    text_rows = list(has_text.index[has_text])
    return data.drop(text_rows)