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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 is_dependant(package, project_name):
 """Determine whether `package` is a dependant of `project_name`."""

    for requirement in package.requires():
        # perform case-insensitive matching
        if requirement.project_name.lower() == project_name.lower():
            return True
    return False