import pandas as pd
import matplotlib.pyplot as plt
from matplotlib.ticker import MaxNLocator

-----------------------------------------------------------------
ModuleNotFoundError             Traceback (most recent call last)
Cell In[1], line 1
----> 1 import pandas as pd
      2 import matplotlib.pyplot as plt
      3 from matplotlib.ticker import MaxNLocator

ModuleNotFoundError: No module named 'pandas'

def fib_list(n: int) -> list[int]:
    fibs = [0, 1]
    for _ in range(2, n):
        fibs.append(fibs[-1] + fibs[-2])
    return fibs

def plot_fib(n: int) -> None:
    fibs = fib_list(n)
    df = pd.DataFrame({"n": list(range(1, n+1)), "fib": fibs})

    # Plot inline
    plt.figure(figsize=(10, 4))
    plt.xlabel("n (index)")
    plt.ylabel("Fib(n)")
    plt.plot(df["n"], df["fib"], marker="o")
    plt.xlabel("n (index)")
    plt.ylabel("Fib(n)")
    plt.title(f"First {n} Fibonacci numbers")
    plt.grid(True)
    ax = plt.gca()
    ax.xaxis.set_major_locator(MaxNLocator(integer=True))
    ax.yaxis.set_major_locator(MaxNLocator(integer=True))
    plt.tight_layout()
    plt.show()

n = 20
plot_fib(n)

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NameError                       Traceback (most recent call last)
Cell In[5], line 2
      1 n = 20
----> 2 plot_fib(n)

Cell In[4], line 3, in plot_fib(n)
      1 def plot_fib(n: int) -> None:
      2     fibs = fib_list(n)
----> 3     df = pd.DataFrame({"n": list(range(1, n+1)), "fib": fibs})
      5     # Plot inline
      6     plt.figure(figsize=(10, 4))

NameError: name 'pd' is not defined