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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 find_requirements(filename):
 """ Find requirements in file. """

    import string
    content = read(filename)
    requirements = []
    for line in content.splitlines():
        line = line.strip()
        if line and line[:1] in string.ascii_letters:
            requirements.append(line)
    return requirements